8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 or 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): May 17, 2011

CSG SYSTEMS INTERNATIONAL, INC.

(Exact name of registrant as specified in its charter)

Delaware	0-27512	47-0783182
(State or other jurisdiction of incorporation)	(Commission File Number)	(IRS Employer Identification No.)

9555 Maroon Circle, Englewood, CO	80112
(Address of principal executive offices)	(Zip Code)

Registrant’s telephone number, including area code: (303) 200-2000

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

¨ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On May 17, 2011, the stockholders of CSG Systems International, Inc. (the “Company” or “CSG”) approved the material terms of the revised performance goals that may apply to awards to certain executive officers under the CSG Systems International, Inc. Performance Bonus Program (the “Bonus Program”).

The Bonus Program, which is administered by the Compensation Committee of CSG’s Board of Directors (the “Compensation Committee”), provides for the payment of annual cash bonus awards for: (i) the persons designated as executive officers of the Company; and (ii) any other employee of the Company who is or may be a “covered employee” of the Company as defined in Section 162(m)(3) of the Internal Revenue Code of 1986, as amended. The Bonus Program requires that, no later than ninety days after the beginning of each calendar year, the Compensation Committee establish in writing an annual performance bonus plan (the “Annual Bonus Plan”) that includes: (i) one or more performance goals that must be attained in order for a participant to receive a bonus award for such year; and (ii) the method, in terms of an objective formula or standard, for computing the amount of the bonus award if applicable performance goals are attained. The Bonus Program specifies the objective business criteria that the Annual Bonus Plan’s performance goals are required to be based upon. Prior to the payment of bonus awards, the Compensation Committee must certify in writing that the applicable performance goals have been attained.

Under the 2011 Annual Bonus Plan, established in writing by the Compensation Committee and approved by the CSG’s Board of Directors on March 1, 2011, the maximum amount of compensation payable as a performance award under the Bonus Program to a participant for any calendar year is 200% of the annual base salary of such participant as of the last day of such calendar year, based on the achievement of their individual performance objectives and the achievement of pre-established Company performance goals. The 2011 Annual Bonus Plan’s performance goals are based on CSG’s targeted 2011 revenue and 2011 operating income. If the lower end of the range of either of the 2011 Annual Bonus Plan performance goals is not achieved, then no bonus awards will be paid under the 2011 Annual Bonus Plan regardless of the achievement of individual performance objectives.

Item 5.07. Submission of Matters to a Vote of Security Holders.

On May 17, 2011, CSG held its Annual Meeting of Stockholders. The proposals voted upon at the meeting, which are more fully described in CSG’s proxy statement dated April 8, 2011 (the “2011 Proxy”), and the results of the vote were as follows:

Proposal 1: Election of Directors. The table below shows the results of the stockholders’ vote for the election of the Class II Directors:

Name of Director	For		Withheld		Non Votes
Ronald H. Cooper		26,493,150		804,804		2,641,064
John L. M. Hughes		26,886,314		411,640		2,641,064
Bernard W. Reznicek		26,725,715		572,239		2,641,064
Donald V. Smith		26,515,152		782,802		2,641,064

Proposal 2: Advisory Vote on Executive Compensation. The table below shows the results of a non-binding advisory vote on our executive compensation program:

For	Against	Abstain	Non Votes
25,686,614	1,490,106	121,234	2,641,064

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Proposal 3: Advisory Vote on the Frequency of Advisory Votes on Executive Compensation. The table below shows the results of a non-binding advisory vote on the frequency of executive compensation program advisory votes:

1 Year	2 Years	3 Years	Abstain	Non Votes
22,013,335	223,112	4,949,724	111,783	2,641,064

While this advisory vote on the frequency of future advisory votes on CSG’s compensation for its named executive officers is not binding on CSG’s Board of Directors (the “Board”), the Board will carefully evaluate the results of such vote at a future meeting and make a determination as to whether it will submit future advisory votes on executive compensation for consideration by stockholders every one, two, or three years. CSG will amend this Current Report on Form 8-K to provide information regarding such determination.

Proposal 4: Approval of the Performance Goals Under the Performance Bonus Program. A proposal to approve the material terms of the revised performance goals that may apply to awards to certain executive officers under the CSG Systems International, Inc. Performance Bonus Program, was adopted with the votes shown:

For	Against	Abstain	Non Votes
26,343,867	856,407	97,680	2,641,064

Proposal 5: Approval of the Amended and Restated 2005 Stock Incentive Plan. A proposal to approve the Amended and Restated CSG Systems International, Inc. 2005 Stock Incentive Plan was adopted with the votes shown:

For	Against	Abstain	Non Votes
20,634,682	6,563,168	100,104	2,641,064

Proposal 6: Approval of the Second Amended and Restated 1996 Employee Stock Purchase Plan. A proposal to approve the Second Amended and Restated CSG Systems International, Inc. 1996 Employee Stock Purchase Plan was adopted with the votes shown:

For	Against	Abstain	Non Votes
26,636,089	562,191	99,674	2,641,064

Proposal 7: Ratification of Appointment of Independent Registered Public Accounting Firm. A proposal to ratify the appointment of KPMG LLP as CSG’s independent registered public accounting firm for 2011 was adopted with the votes shown:

For	Against	Abstain
29,643,148	285,845	10,025

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits

10.02	Second Amended and Restated 1996 Employee Stock Purchase Plan, as adopted on May 17, 2011
10.04	CSG Systems International, Inc. 2005 Stock Incentive Plan, as adopted on May 17, 2011
10.05	CSG Systems International, Inc. Performance Bonus Program, as adopted on May 17, 2011

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: May 23, 2011

CSG SYSTEMS INTERNATIONAL, INC.
By:	/s/ Randy R. Wiese
	Randy R. Wiese,
	Chief Financial Officer and
	Principal Accounting Officer

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CSG Systems International, Inc.

Form 8-K

Exhibit Index

10.02	Second Amended and Restated 1996 Employee Stock Purchase Plan, as adopted on May 17, 2011
10.04	CSG Systems International, Inc. 2005 Stock Incentive Plan, as adopted on May 17, 2011
10.05	CSG Systems International, Inc. Performance Bonus Program, as adopted on May 17, 2011

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EX-10.02

Exhibit 10.02

CSG SYSTEMS INTERNATIONAL, INC.

SECOND AMENDED AND RESTATED 1996 EMPLOYEE STOCK PURCHASE PLAN

ARTICLE I

GENERAL

1.1 Purpose of the Plan. The purpose of the CSG Systems International, Inc. Second Amended and Restated 1996 Employee Stock Purchase Plan (the “Plan”) is to provide Eligible Employees of the Company and its Designated Subsidiaries with a program for the regular purchase of Shares from the Company through periodic payroll deductions and dividend reinvestments, thereby giving Participants the opportunity to acquire a proprietary interest in the success of the Company.

1.2 Definitions. For purposes of the Plan, the following words and phrases shall have the meanings indicated, unless the context clearly indicates otherwise:

(a) “Adjusted Price” means an amount equal to eighty-five percent (85%) of the Fair Market Value on the last trading day of the Purchase Period for which an Adjusted Price is being determined.

(b) “Agent” means the independent agent appointed pursuant to Section 1.4.

(c) “Board” means the board of directors of the Company.

(d) “Company” means CSG Systems International, Inc., a Delaware corporation.

(e) “Designated Subsidiary” means a Subsidiary designated by the Board for participation in the Plan.

(f) “Eligible Employee” means a person who is of majority age in his or her domicile state or other applicable jurisdiction and is a full-time or part-time employee of the Company or a Designated Subsidiary, except that a temporary employee and an employee who has been designated by the Board of Directors of the Company as an executive officer of the Company or is otherwise subject to the provisions of Section 16(b) of the Securities Exchange Act of 1934 shall not be eligible to participate in the Plan.

(g) “Fair Market Value” means the last sale price of the Shares as quoted on the Nasdaq Stock Market on the trading day for which the determination is being made, or, in the event that no such sale takes place on such day, the average of the reported closing bid and asked prices on such day, or, if the Shares are

listed on another national securities exchange, the last reported sale price on the principal national securities exchange on which the Shares are listed or admitted to trading on the trading day for which the determination is being made, or, if no such reported sale takes place on such day, the average of the closing bid and asked prices on such day on the principal national securities exchange on which the Shares are listed or admitted to trading, or, if the Shares are neither quoted on the Nasdaq Stock Market nor listed or admitted to trading on another national securities exchange, the average of the closing bid and asked prices in the over-the-counter market on the day for which the determination is being made as reported through Nasdaq, or, if bid and asked prices for the Shares on such day are not reported through Nasdaq, the average of the bid and asked prices for such day as furnished by any New York Stock Exchange member firm regularly making a market in the Shares selected for such purpose by the Chief Executive Officer of the Company, or, if none of the foregoing is applicable, the fair market value of the Shares as determined in good faith by the Chief Executive Officer of the Company in his sole discretion.

(h) “Participant” means an Eligible Employee who has elected to participate in the Plan pursuant to Section 2.1.

(i) “Purchase Period” means the period established pursuant to Section 2.2 which determines the times for the issuance of Shares by the Company to the Agent pursuant to Section 2.2

(j) “Shares” means shares of Common Stock, $0.01 par value per share, of the Company.

(k) “Subsidiary” means a corporation or other entity of which not less than 50% of the voting shares or other voting interests are held by the Company or a Subsidiary, whether or not such corporation or other entity now exists or hereafter is organized or acquired by the Company or a Subsidiary. The plural form of such word is “Subsidiaries”.

1.3 Effective Date and Term of Plan. The original effective date of the Plan was September 1, 1996. This second amendment and restatement of the Plan shall become effective upon its approval by the stockholders of the Company at the 2011 annual meeting of the stockholders of the Company. The Plan shall remain in effect indefinitely, subject to termination by the Board as of the end of any Purchase Period and subject to the provisions of Section 1.5.

1.4 Appointment and Removal of the Agent. The Company shall appoint an independent bank, trust company, brokerage firm, or other financial institution or an affiliate thereof to administer the Plan (including but not limited to the establishment of such procedures as reasonably may be necessary to accomplish such administration in a manner consistent with the purposes of the Plan), keep the records of the Plan reflecting the interests of Participants, hold Shares acquired under the Plan on behalf of Participants, and generally act as the agent of

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Participants in the manner and to the extent provided in the Plan. The Agent may resign at any time by giving written notice of such resignation to the Company at least thirty (30) days prior to the effective date of such resignation. The Company may remove the Agent at any time by giving written notice of such removal to the Agent at least thirty (30) days prior to the effective date of such removal. In the event of the resignation or removal of the Agent, the Company promptly shall appoint a new Agent. The Company shall provide the names and addresses of all Participants to the Agent to facilitate direct communications by the Agent to the Participants.

1.5 Shares Available Under the Plan. The maximum number of shares which the Company may issue under the Plan on and after the date of the 2011 annual meeting of stockholders of the Company is the sum of (a) the number of Shares which were available for issuance under the Plan as of the day immediately preceding the date of the 2011 annual meeting of stockholders of the Company, plus (b) 750,000 Shares; and the Company shall reserve and keep available for issuance under the Plan such maximum number of shares. In the event of an increase in the number of outstanding Shares by reason of a stock dividend or stock split, the number of Shares then remaining available for issuance under the Plan shall be increased proportionately.

1.6 Action by the Company. Unless otherwise expressly provided by the Plan or the Board, whenever an action is required by or permitted to the Company under the Plan and is not expressly required to be taken by the Board, such action shall be taken by the Chief Executive Officer of the Company or his or her delegate.

ARTICLE II

PLAN PARTICIPATION

2.1 Enrollment and Payroll Deductions. Participation in the Plan is voluntary. An Eligible Employee may elect to participate in the Plan by completing the necessary enrollment steps prescribed by the Company to authorize periodic payroll deductions by the Company from such Eligible Employee’s wages of the periodic amount specified by such Eligible Employee. Payroll deductions with respect to an Eligible Employee shall commence as soon as administratively practicable after the enrollment and payroll deduction authorization of such Eligible Employee is received and accepted by the Company. If a Participant’s wages are paid on a biweekly schedule, then the biweekly payroll deduction amount specified by such Participant in his or her payroll deduction authorization must be a minimum of $10.00 and may not exceed $500.00; in the case of Participants whose compensation is paid in a currency other than United States dollars, the applicable limits shall be the approximate equivalents of such minimum and maximum amounts fixed from time to time by the Company in administratively convenient units of such other currency. If a Participant’s wages are paid on a schedule other than biweekly, then the periodic payroll deductions referred to in this Section 2.1 shall be made with respect to such Participant in accordance with such schedule as reflected in such Participant’s payroll deduction authorization; and the Company shall proportionately adjust the minimum and maximum permitted payroll deductions applicable to such Participant. A Participant may change his or her periodic payroll deduction amount by completing the necessary steps prescribed by the Company; such change shall

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be effective as soon as administratively practicable after the change form is received and accepted by the Company. A Participant may cease participation in the Plan as of any payroll date by giving notice of such cessation to the Company in such form as the Company may specify at least fifteen (15) days prior to such payroll date. The Agent shall continue to maintain the Plan account of a Participant who ceases participation in the Plan until such Participant instructs the Agent either to issue the Shares held in such Plan account to such Participant or to sell such Shares and remit the net proceeds of such sale to such Participant as provided in Section 2.5.

2.2 Purchase Period and Issuance of Shares to Agent. Unless the Company establishes a different Purchase Period, the Purchase Period shall be each calendar month. The Company may change the Purchase Period from time to time, but in no event shall the Purchase Period be longer than six (6) calendar months. If the Company elects to change the Purchase Period, then the Company will notify each then Participant of such impending change, in writing or electronically, not less than sixty (60) days prior to the effective date of such change. On the last business day of each Purchase Period, the Company shall notify the Agent in written or electronic form of the aggregate United States dollar amount withheld for each Participant during such Purchase Period and shall instruct the transfer agent for the Shares to issue to the Agent (in such form or nominee name as the Agent may direct) as an original issuance of authorized but unissued Shares or as the reissuance of Shares held by the Company as treasury shares (and shall provide such transfer agent with such additional documentation as may be required for such purpose) that number of full Shares which is equal to (a) the aggregate United States dollar amount withheld pursuant to the Plan for all Participants during such Purchase Period divided by (b) the Adjusted Price; any portion of such aggregate dollar amount that is insufficient to purchase a full Share shall be carried over to the next Purchase Period. Upon the issuance or reissuance of such number of full Shares, the amount referred to in clause (a) of the preceding sentence (less any amount carried over to the following Purchase Period) shall be deemed to have been paid to and received by the Company, and shall be appropriately reflected on the books of the Company, as the consideration for such number of newly issued or reissued full Shares. For purposes of determining the United States dollar amount withheld from the wages of Participants whose compensation is paid in a currency other than United States dollars, the amount withheld in such other currency shall be converted to United States dollars on the basis of the applicable exchange rate quoted in The Wall Street Journal or another reliable source for the next-to-the-last business day of the Purchase Period involved.

2.3 Allocation of Shares Among Participants. The Agent shall establish and maintain a separate Plan account for each Participant and shall allocate the Shares acquired by the Agent pursuant to Section 2.2 for a particular Purchase Period among the Plan accounts of those Participants whose payroll deductions provided the funds used to acquire such Shares. Such allocation shall be made in the Plan records maintained by the Agent in proportion to the United States dollar amount of funds so provided by each Participant and, if fractional shares are involved, shall be made to three decimal places. Subject to the provisions of Section 2.5, the Agent shall hold in its name or the name of its nominee, for the benefit of all Participants, all shares acquired under the Plan. The Agent shall regularly make available to each Participant, either in written or electronic form, current information with respect to the Participant’s Plan account showing acquisitions of Shares, dividends credited, sales or issuances of Shares, any applicable commissions or fees charged to such Participant, and the number of Shares then held.

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2.4 Dividends and Distributions. Dividends and other distributions by the Company with respect to Shares held by the Agent under the Plan shall be allocated or otherwise dealt with by the Agent as follows:

(a) Cash Dividends. Cash dividends received by the Agent on Shares allocated to Participants’ Plan accounts shall be used by the Agent to acquire additional Shares for such Participants by remitting the aggregate amount of such cash dividends to the Company to be added to the amount applied to the next acquisition of Shares from the Company pursuant to Section 2.2.

(b) Stock Dividends and Stock Splits. Stock dividends and stock splits shall be credited to Participants having Shares allocated to their Plan accounts to the extent that such stock dividends and stock splits are attributable to such Shares.

(c) Stock Rights. If the Company makes available to its stockholders generally rights to subscribe to additional Shares or other securities, then such rights accruing on Shares held by the Agent under the Plan shall be sold by the Agent and the net proceeds of such sale shall be applied to the acquisition from the Company of additional Shares for Participants in the same manner as cash dividends are applied.

2.5 Issuance of Shares to Participant; Sale of Shares for Participant. Upon the request of a Participant, the Agent will arrange for some or all of the Shares in such Participant’s Plan account to be issued to such Participant as promptly as practicable. Upon the issuance of such Shares, such Participant’s Plan account will be appropriately debited. Upon the request of a Participant, the Agent will sell for the account of such Participant any or all of the Shares in such Participant’s Plan account and shall remit the proceeds of such sale, net of applicable brokerage commissions (if any), to such Participant as promptly as practicable. If a Participant requests that sale proceeds be remitted to such Participant in a currency other than United States dollars, then the requested currency exchange will be made at the prevailing rate for transactions of the size involved as determined in the sole discretion of the Agent or its designee for such purpose, and such Participant will bear all expenses incurred by the Agent in effecting such currency exchange. The Agent shall process transactions involving fractional Shares in such manner as the Agent deems appropriate for the particular transaction. Requests by Participants pursuant to this Section 2.5 may be made in writing or by such electronic or other means as the Agent may provide.

2.6 Voting Rights. A Participant will have the right to vote the Shares in his or her Plan account in accordance with the Agent’s customary procedures for the voting of shares held in “street name” or other similar types of accounts; however, a Participant is not a stockholder of record of the Company with respect to any Shares held in such Participant’s Plan account.

2.7 Expenses. The Company will bear all of the expenses of administering the Plan, including but not limited to the Agent’s fees and any transfer taxes and expenses of issuing Shares to Participants. However, a Participant will bear any expenses incurred by the Agent in selling Shares held for such Participant under the Plan, including but not limited to applicable brokerage commissions and currency exchange expenses.

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2.8 Termination of Eligibility. If a Participant ceases to be eligible to participate in the Plan for any reason, including but not limited to the termination of such Participant’s employment by the Company or a Designated Subsidiary, then such Participant may no longer participate in the Plan through payroll deductions. If a Participant ceases to be eligible to participate in the Plan for a reason other than such Participant’s death, then the Agent shall maintain such Participant’s Plan account pending the Agent’s receipt of instructions either from the Participant or from the Company as to the issuance or sale of the Shares in such Plan account in accordance with Section 2.5 If a Participant dies, then the Agent shall maintain the deceased Participant’s Plan account pending the Agent’s receipt of instructions as to the disposition of such Plan account from the duly authorized representative of the deceased Participant’s estate.

2.9 Termination of Plan. If the Company terminates the Plan, then the Agent shall arrange for the full Shares in a Participant’s Plan account to be issued to such Participant as promptly as practicable and shall sell for the account of such Participant any fractional Shares in such Participant’s Plan account and remit the proceeds of such sale, net of applicable brokerage commissions (if any), to such Participant as promptly as practicable. However, in its discretion, the Company may provide additional alternatives for the disposition of the Shares in a Participant’s Plan account upon the termination of the Plan.

2.10 Rules for Foreign Jurisdictions. Notwithstanding any other provisions of the Plan to the contrary, the Company and, to the extent permitted under applicable law, the Chief Executive Officer of the Company or his or her delegate may, in its or his or her sole discretion, amend or vary the terms of the Plan in order to conform such terms to the tax, employment, securities law, or other requirements of each non-U.S. jurisdiction where a Designated Subsidiary is located or to accomplish the purpose of the Plan with respect to the Eligible Employees employed in such non-U.S. jurisdiction. Each of the Company and, to the extent permitted under applicable law, the Chief Executive Officer of the Company or his or her delegate may, where it or he or she deems appropriate in its or his or her sole discretion, establish one or more sub-plans of the Plan for such purposes. The Company and, to the extent permitted under applicable law, the Chief Executive Officer of the Company or his or her delegate may, in its or his or her sole discretion, establish administrative rules and procedures to facilitate the operation of the Plan in such non-U.S. jurisdictions. For purposes of clarity, the terms of the Plan which vary for a particular non-U.S. jurisdiction or the terms of any sub-plan of the Plan for a particular non-U.S. jurisdiction shall be reflected in a written addendum to the Plan or a written sub-plan document for such non-U.S. jurisdiction.

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ARTICLE III

MISCELLANEOUS

3.1 Interpretation and Administration. The Chief Executive Officer of the Company or his or her delegate shall have the authority from time to time (a) to establish rules and regulations for the operation of the Plan, (b) to interpret the Plan, (c) to decide any and all questions which may arise in connection with the Plan, and (d) to modify any of the administrative provisions of the Plan to facilitate the proper and efficient administration of the Plan. Any delegate of the Chief Executive Officer of the Company for purposes of the Plan shall not make any discretionary decision which pertains directly to such delegate as a Participant and not to all Participants generally.

3.2 Nonassignability. A Participant shall not have any right to sell, assign, transfer, pledge, or otherwise encumber or convey such Participant’s Plan account or any interest therein except pursuant to Section 2.5. No Plan account shall be subject to attachment, garnishment, or seizure for the payment of any debts, judgments, alimony, child support, or separate maintenance owed by a Participant nor be transferable by operation of law in the event of a Participant’s bankruptcy or insolvency.

3.3 Employment Rights. An Eligible Employee’s election to participate in the Plan and the Company’s acceptance of such Eligible Employee’s enrollment in the Plan shall not be deemed to constitute a contract of employment between such Eligible Employee and the Company or any Designated Subsidiary. No provision of the Plan shall be deemed to give any Participant any right (i) to be retained in the employ or other service of the Company or any Designated Subsidiary for any specific length of time, (ii) to interfere with the right of the Company or any Designated Subsidiary to discipline or discharge the Participant at any time, (iii) to hold any particular position or responsibility with the Company or any Designated Subsidiary, or (iv) to receive any particular compensation from the Company or any Designated Subsidiary.

3.4 Withholding; Payroll Taxes. To the extent required by applicable laws and regulations in effect at the time payroll deductions pursuant to the Plan are made from a Participant’s wages, the Company or the Designated Subsidiary by whom such Participant’s wages are paid shall withhold from the remaining portion of such wages any taxes or other obligations required to be withheld from such wages by federal, state, local, or other laws by reason of such payroll deductions and the purchase of Shares under the Plan for the benefit of such Participant at a price less than Fair Market Value.

3.5 Transfer Upon Death. The Plan account of a Participant may be transferred by will or the laws of descent and distribution upon the death of such Participant, but the Company may require any transferee of a deceased Participant’s Plan account promptly to elect either the issuance or the sale of all of the Shares in such Plan account pursuant to Section 2.5.

3.6 Amendment. The Board may amend the Plan at any time in whole or in part without terminating the Plan; however, no amendment of the Plan shall decrease the number of Shares already credited to the Plan accounts of Participants. If the Board changes the discount from Fair Market Value at which Shares are to be acquired under the Plan, then the Company shall not implement such change until the then Participants have been notified of such change and have been given a reasonable opportunity to cease participation in the Plan.

3.7 Plan Year. The plan year shall be the calendar year, except that the first plan year began on September 1, 1996, and ended on December 31, 1996.

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3.8 Securities Law Compliance. The obligation of the Company to sell and issue Shares pursuant to the Plan is subject to the approval of any governmental authority required in connection with the authorization, issuance, or sale of such Shares and to the satisfaction of any legal preconditions to such issuance or sale.

3.9 Governing Law. The provisions of the Plan shall be governed by and construed according to the laws of the State of Delaware.

3.10 Number and Gender. Unless the context otherwise requires, for all purposes of the Plan, words in the singular include their plural, words in the plural include their singular, and words of one gender include the other genders.

3.11 Successors. The provisions of the plan shall be binding upon and inure to the benefit of the Company, each Participant, and their respective heirs, personal representatives, successors, and permitted assigns (if any).

3.12 Section Titles. The titles of the various sections of the Plan are for convenient reference only and shall not be considered in the interpretation of the Company.

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EX-10.04

Exhibit 10.04

CSG SYSTEMS INTERNATIONAL, INC.

AMENDED AND RESTATED 2005 STOCK INCENTIVE PLAN

1. Purpose. The purpose of the CSG Systems International, Inc. 2005 Stock Incentive Plan (the “Plan”) is to foster and promote the long-term financial success of the Company and its Subsidiaries and thereby increase stockholder value by providing incentives to those officers and other key employees of the Company and its Subsidiaries who are likely to be responsible for achieving such financial success and by attracting and compensating knowledgeable and experienced non-employee directors of the Company whose services on the Board and its committees can assist such officers and other key employees in the achievement of such financial success.

2. Certain Definitions.

“Board” means the Board of Directors of the Company.

“Code” means the Internal Revenue Code of 1986, as amended from time to time, or any successor thereto. References to a particular section of the Code shall include any regulations issued under such section.

“Committee” shall have the meaning provided in Section 3 of the Plan.

“Common Stock” means the Common Stock, $0.01 par value per share, of the Company.

“Company” means CSG Systems International, Inc., a Delaware corporation.

“Disability” means (i) with respect to the exercise of an Incentive Stock Option after termination of employment, a disability within the meaning of Section 22(e)(3) of the Code and (ii) for all other purposes, a mental or physical condition which, in the opinion of the Committee, renders a grantee unable or incompetent to carry out the job responsibilities which such grantee held or the tasks to which such grantee was assigned (or, in the case of a non-employee director of the Company, the services in such capacity which such non-employee director is expected to perform) at the time the disability was incurred and which is expected to be permanent or for an indefinite duration exceeding one year.

“Exchange Act” means the Securities Exchange Act of 1934, as amended from time to time.

“Fair Market Value” means, as determined by the Committee, the last sale price of the Common Stock as quoted on the Nasdaq Stock Market on the trading day for which the determination is being made, or, in the event that no such sale takes place on such day, the

average of the reported closing bid and asked prices on the Nasdaq Stock Market on such day, or, if the Common Stock of the Company is listed on another national securities exchange, the last reported sale price on the principal national securities exchange on which the Common Stock is listed or admitted to trading on the trading day for which the determination is being made, or, if no such reported sale takes place on such day, the average of the closing bid and asked prices on such day on the principal national securities exchange on which the Common Stock is listed or admitted to trading, or, if the Common Stock is not quoted on the Nasdaq Stock Market nor listed or admitted to trading on another national securities exchange, the average of the closing bid and asked prices in the over-the-counter market on the day for which the determination is being made as reported through Nasdaq, or, if bid and asked prices for the Common Stock on such day are not reported through Nasdaq, the average of the bid and asked prices for such day as furnished by any New York Stock Exchange member firm regularly making a market in the Common Stock selected for such purpose by the Committee, or, if none of the foregoing is applicable, then the fair market value of the Common Stock as determined in good faith by the Committee in its sole discretion.

“Incentive Stock Option” means any stock option intended to qualify as an “incentive stock option” within the meaning of Section 422 of the Code.

“Non-Qualified Stock Option” means any stock option that is not intended to be an Incentive Stock Option, including any stock option that provides (as of the time such option is granted) that it will not be treated as an Incentive Stock Option.

“Parent Corporation” means any corporation (other than the Company) in an unbroken chain of corporations ending with the Company if, at the time of the granting of the option, each of the corporations other than the Company owns stock possessing 50% or more of the total combined voting power of all classes of stock in one of the other corporations in such chain.

“Performance Unit Award” means an award granted pursuant to Section 8.

“Plan Year” means the twelve-month period beginning on January 1 and ending on December 31; provided, that the first Plan Year shall be a short Plan Year beginning on the date on which the Plan is approved by the stockholders of the Company and ending on December 31 of the calendar year during which such stockholder approval occurs.

“Restricted Stock Award” means an award of Common Stock granted pursuant to Section 9.

“Restricted Stock Unit Award” means an award granted pursuant to Section 10.

“Rule 16b-3” means Rule 16b-3 under the Exchange Act, as in effect from time to time.

“Stock Appreciation Right” means an award granted pursuant to Section 7.

“Stock Bonus Award” means an award of Common Stock granted pursuant to Section 11.

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“Stock Option” means any option to purchase Common Stock granted pursuant to Section 6.

“Subsidiary” means (i) as it relates to Incentive Stock Options, any corporation (other than the Company) in an unbroken chain of corporations beginning with the Company if, at the time of the granting of the option, each of the corporations (other than the last corporation in the unbroken chain) owns stock possessing 50% or more of the total combined voting power of all classes of stock in one of the other corporations in such chain and (ii) for all other purposes, a corporation or other entity, domestic or foreign, of which not less than 50% of the voting shares or other voting interests are held by the Company or by a Subsidiary, whether or not such corporation or other entity now exists or hereafter is organized or acquired by the Company or by a Subsidiary. The plural form of such word is “Subsidiaries”.

3. Administration. The Plan shall be administered by a committee composed solely of two or more members of the Board (the “Committee”) selected by the Board, each of whom shall qualify as a “Non-Employee Director” within the meaning of Rule 16b-3 and as an “outside director” within the meaning of Section 162(m) of the Code.

The Committee shall have authority to grant to eligible employees of the Company and its Subsidiaries and to non-employee directors of the Company, pursuant to the terms of the Plan, (a) Stock Options, (b) Stock Appreciation Rights, (c) Performance Unit Awards, (d) Restricted Stock Awards, (e) Restricted Stock Unit Awards, (f) Stock Bonus Awards, or (g) any combination of the foregoing; provided, that the Committee may not grant Incentive Stock Options, Performance Unit Awards, or Stock Bonus Awards to non-employee directors of the Company.

Subject to the applicable provisions of the Plan, the Committee shall have authority to interpret the provisions of the Plan and to decide all questions of fact arising in the application of such provisions; to select the officers and other key employees of the Company and its Subsidiaries and the non-employee directors of the Company to whom awards or options shall be granted under the Plan; to determine whether and to what extent awards or options shall be granted under the Plan; to determine the types of awards and options to be granted under the Plan and the amount, size, terms, and conditions of each such award or option; to determine the time when awards or options shall be granted under the Plan; to determine whether, to what extent, and under what circumstances the payment of Common Stock and other amounts payable with respect to an award granted under the Plan shall be deferred either automatically or at the election of the grantee; to determine the Fair Market Value of the Common Stock from time to time; to authorize persons to execute on behalf of the Company any agreement required to be entered into under the Plan; to adopt, alter, and repeal such administrative rules, guidelines, and practices governing the Plan as the Committee from time to time shall deem advisable; and to make all other determinations and take all other actions necessary or advisable for the administration of the Plan.

Unless otherwise expressly provided in the Plan or by applicable law, all decisions and determinations made by the Committee in the administration and interpretation of the Plan or with respect to any ambiguous or disputed terms of any award or option shall be made in the sole

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discretion of the Committee and shall be final and binding on all persons, including but not limited to the Company and its Subsidiaries, the officers and other key employees of the Company and its Subsidiaries and the non-employee directors of the Company to whom awards and options are granted under the Plan, the heirs and legal representatives of such officers, key employees, and non-employee directors, and the personal representatives and beneficiaries of the estates of such officers, key employees, and non-employee directors.

The Committee may, in its sole discretion, vary the provisions of the Plan (except the provisions of Sections 4, 13, 14, 21 (other than to require a grantee’s consent to an amendment of an outstanding option or award), and 24 of the Plan) in order to conform such provisions to the legal requirements of each non-U.S. jurisdiction where a Subsidiary is located or to better accomplish the purpose of the Plan (including but not limited to the tax treatment of grantees of awards and options) with respect to (i) persons employed in such non-U.S. jurisdictions who are eligible to receive awards and options under the Plan and (ii) non-employee directors of the Company who reside in non-U.S. jurisdictions. The Committee may, where it deems appropriate in its sole discretion, establish one or more sub-plans for such purposes; and the Committee may, in its sole discretion, establish administrative rules and procedures to facilitate the operation of the Plan or such sub-plans in such non-U.S. jurisdictions. For purposes of clarity, the terms of the Plan which will vary in a particular non-U.S. jurisdiction shall be reflected in a written addendum to the Plan for such non-U.S. jurisdiction.

The Committee may delegate to any officer or officers of the Company any of the Committee’s duties, powers, and authorities under the Plan upon such conditions and with such limitations as the Committee may determine; provided, that only the Committee may select for awards or options under the Plan, and make grants of awards or options under the Plan to, (i) officers and other key employees of the Company or any Subsidiary who are subject to Section 16 of the Exchange Act at the time of such selection or the making of such a grant and (ii) non-employee directors of the Company.

4. Common Stock Subject to the Plan. Subject to adjustment pursuant to Section 20, the maximum number of shares of Common Stock which may be issued under the Plan is 15,800,000; and the Company shall reserve and keep available for issuance under the Plan such maximum number of shares, subject to adjustment pursuant to Section 20. Such shares may consist in whole or in part of authorized and unissued shares or treasury shares or any combination thereof. Shares of Common Stock subject to a Stock Option or a Stock Appreciation Right granted under the Plan shall be counted against the maximum number of shares of Common Stock which may be issued under the Plan as one share for each share subject to the Stock Option or the Stock Appreciation Right. Shares awarded under the Plan as a Performance Unit Award, Restricted Stock Award, Restricted Stock Unit Award, or Stock Bonus Award shall be counted against the maximum number of shares of Common Stock which may be issued under the Plan as two shares for each one share granted as or subject to such Award. Subject to adjustment pursuant to Section 20, the aggregate number of shares of Common Stock subject to (i) Stock Options, (ii) Stock Appreciation Rights, (iii) Performance Unit Awards, (iv) Restricted Stock Awards, (v) Restricted Stock Unit Awards, or (vi) Stock Bonus Awards granted under the Plan in any Plan Year to any individual may not exceed 600,000, with shares awarded under the Plan to such individual as a Performance Unit Award,

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Restricted Stock Award, Restricted Stock Unit Award, or Stock Bonus Award being counted against such aggregate number as two shares for each one share granted as or subject to such Award. Except as otherwise provided in the Plan, any shares as to which a Stock Option or Stock Appreciation Right expires for any reason or terminates unexercised shall be available again for the grant of awards or options under the Plan. If any shares of Common Stock granted as a Restricted Stock Award or subject to a Restricted Stock Unit Award are forfeited, cancelled, or otherwise reacquired by the Company by reason of the failure of such shares to vest in the grantee of such Award, then the number of shares of Common Stock which then remain available for issuance under the Plan shall be increased by two shares for each one share so forfeited, cancelled, or otherwise reacquired by the Company. Shares of Common Stock retained by the Company in full or partial payment of an option exercise price pursuant to Section 6(d)(ii)(B) or withheld by the Company in satisfaction of any federal, state, or local tax withholding requirement shall not be available again for the grant of awards or options under the Plan. If a Stock Appreciation Right is exercised by a grantee or a Restricted Stock Unit Award vests in a grantee and the Company pays the award to the grantee entirely in cash, then the shares covered by the Stock Appreciation Right or Restricted Stock Unit Award as to which such exercise or vesting occurs shall be available again for the grant of awards or options under the Plan.

5. Eligibility to Receive Awards and Options. Awards and options may be granted under the Plan to those officers and other key employees of the Company or any Subsidiary who are responsible for or contribute to, or are likely to be responsible for or contribute to, the management, growth, and success of the Company or any Subsidiary and to non-employee directors of the Company. The granting of an award or option under the Plan to an officer or other key employee of the Company or any Subsidiary shall conclusively evidence the Committee’s determination that such grantee meets one or more of the criteria referred to in the preceding sentence.

6. Stock Options. A Stock Option may be an Incentive Stock Option or a Non-Qualified Stock Option. To the extent that any Stock Option does not qualify as an Incentive Stock Option, it shall constitute a separate Non-Qualified Stock Option. Stock Options may be granted alone or in addition to other awards made under the Plan. Stock Options shall be evidenced by agreements in such form as the Committee shall approve from time to time. The agreements shall contain in substance the following terms and conditions and may contain such additional terms and conditions, not inconsistent with the terms of the Plan, as the Committee shall deem appropriate:

(a) Type of Option. Each option agreement shall identify the Stock Option represented thereby as an Incentive Stock Option or a Non-Qualified Stock Option, as the case may be.

(b) Option Price. The option exercise price per share shall not be less than the Fair Market Value of the Common Stock on the date the Stock Option is granted and in no event shall be less than the par value of the Common Stock.

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(c) Term. Each option agreement shall state the period or periods of time within which the Stock Option may be exercised, in whole or in part, which shall be such period or periods of time as the Committee may determine at the time of the Stock Option grant; provided, that no Stock Option granted under the Plan shall be exercisable more than ten years after the date of its grant; and provided further, that each Stock Option granted under the Plan shall become exercisable one year after the date of its grant, unless the option agreement specifically provides otherwise. The Committee shall have authority to accelerate previously established exercise rights, subject to the requirements set forth in the Plan, under such circumstances and upon such terms and conditions as the Committee shall deem appropriate.

(d) Payment for Shares. The Committee may permit all or part of the payment of the option exercise price to be made (i) in cash, by check, or by wire transfer or (ii) in shares of Common Stock (A) which already are owned by the optionee and which are surrendered to the Company in good form for transfer or (B) which are retained by the Company from the shares of the Common Stock which would otherwise be issued to the optionee upon the optionee’s exercise of the Stock Option. Such shares shall be valued at their Fair Market Value on the date of exercise of the Stock Option. In lieu of payment in fractions of shares, payment of any fractional share amount shall be made in cash or check payable to the Company. The Committee also may provide that the exercise price may be paid by delivering a properly executed exercise notice in a form approved by the Committee together with irrevocable instructions to a broker to promptly deliver to the Company the amount of the applicable sale or loan proceeds required to pay the exercise price. No shares of Common Stock shall be issued to any optionee upon the exercise of a Stock Option until the Company receives full payment therefor as described above.

(e) Rights upon Termination of Employment. In the event that an optionee ceases to be employed either by the Company or by a Subsidiary for any reason other than such optionee’s death or Disability, any rights of the optionee under any Stock Option then in effect immediately shall terminate; provided, that the optionee (or the optionee’s legal representative) shall have the right to exercise the Stock Option during its term within a period of three months after such termination of employment to the extent that the Stock Option was exercisable at the time of such termination or within such other period and subject to such other terms and conditions as may be specified by the Committee. Notwithstanding the foregoing provisions of this Section 6(e), the optionee (and the optionee’s legal representative) shall not have any rights under any Stock Option, and the Company shall not be obligated to sell or deliver shares of Common Stock (or have any other obligation or liability) under any Stock Option, if the Committee shall determine that (i) the employment of the optionee with the Company or any Subsidiary has been terminated for cause or (ii) the optionee has engaged or may engage in employment or activities competitive with the Company or any Subsidiary or contrary, in the opinion of the Committee, to the best interests of the Company or any Subsidiary. In the event of such determination, the optionee (and the optionee’s legal representative) shall have no right under any Stock Option to purchase any shares of Common Stock regardless of whether the optionee (or the optionee’s legal representative) shall have

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delivered a notice of exercise prior to the Committee’s making of such determination. Any Stock Option may be terminated entirely by the Committee at the time of or at any time subsequent to a determination by the Committee under this Section 6(e) which has the effect of eliminating the Company’s obligation to sell or deliver shares of Common Stock under such Stock Option.

In the event that an optionee ceases to be employed either by the Company or by a Subsidiary by reason of such optionee’s Disability, prior to the expiration of a Stock Option and without such optionee’s having fully exercised such Stock Option, such optionee or such optionee’s legal representative shall have the right to exercise such Stock Option during its term within a period of six months after such termination of employment to the extent that such Stock Option was exercisable at the time of such termination or within such other period and subject to such other terms and conditions as may be specified by the Committee.

In the event that an optionee ceases to be employed either by the Company or by a Subsidiary by reason of such optionee’s death, prior to the expiration of a Stock Option and without such optionee’s having fully exercised such Stock Option, the personal representative of such optionee’s estate or the person who acquired the right to exercise such Stock Option by bequest or inheritance from such optionee shall have the right to exercise such Stock Option during its term within a period of twelve months after the date of such optionee’s death to the extent that such Stock Option was exercisable at the time of such death or within such other period and subject to such other terms and conditions as may be specified by the Committee.

The foregoing provisions of this Section 6(e) shall not be applicable to non-employee directors of the Company.

(f) Rights Upon Termination of Service as a Director. Unless the applicable option agreement provides otherwise, if an optionee who is a non-employee director of the Company ceases to be a director of the Company for any reason other than retirement from the Board under the circumstances described in the following paragraph of this Section 6(f) or death, then each outstanding but unexercised Stock Option held by such optionee shall continue to be exercisable only to the extent that it was exercisable at the time that such optionee ceased to be a director of the Company and only until the earlier of (i) three months after such optionee ceased to be a director of the Company or (ii) the expiration of the term of such Stock Option.

Unless the applicable option agreement provides otherwise, if an optionee who is a non-employee director of the Company ceases to be a director of the Company (other than by reason of death) and at the time of such occurrence (the “Retirement Date”) is at least age 65 with ten or more years of service as a non-employee director of the Company or is at least age 70 with five or more years of service as a non-employee director of the Company, then each outstanding but unexercised Stock Option held by such optionee on the Retirement Date shall continue to be or become exercisable in accordance with its terms until the earlier of (i) five years after the Retirement Date or (ii) the expiration of the term of such Stock Option.

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Unless the applicable option agreement provides otherwise, if an optionee who is a non-employee director of the Company dies, then each outstanding but unexercised Stock Option which had been held by such grantee for at least twelve months as of the date of such optionee’s death automatically shall become exercisable in full (if not already exercisable) upon such optionee’s death. Each outstanding but unexercised Stock Option which becomes exercisable pursuant to the preceding sentence and each outstanding but unexercised Stock Option held by such optionee which was exercisable on the date of such optionee’s death may be exercised by the legal representative of such optionee’s estate or by the beneficiaries of such estate to whom such Stock Option is distributed until the earlier of (i) three years after the date of such optionee’s death or (ii) the expiration of the term of such Stock Option.

The foregoing provisions of this Section 6(f) shall be applicable only to non-employee directors of the Company.

To the extent that the aggregate Fair Market Value (determined as of the time the option is granted) of the Common Stock with respect to which Incentive Stock Options granted under the Plan (and all other plans of the Company and its Subsidiaries) become exercisable for the first time by any individual in any calendar year exceeds $100,000, such Stock Options shall be treated as Non-Qualified Stock Options. No Incentive Stock Option shall be granted to any employee if, at the time the option is granted, the employee (in his or her own right or by reason of the attribution rules applicable under Section 424(d) of the Code) owns more than 10% of the total combined voting power of all classes of stock of the Company or any Parent Corporation or Subsidiary unless at the time such option is granted the option price is at least 110% of the Fair Market Value of the stock subject to such Stock Option and such Stock Option by its terms is not exercisable after the expiration of five years from the date of its grant.

7. Stock Appreciation Rights. Stock Appreciation Rights shall enable the grantees thereof to benefit from increases in the Fair Market Value of shares of Common Stock and shall be evidenced by agreements in such form as the Committee shall approve from time to time. The agreements shall contain in substance the following terms and conditions and may contain such additional terms and conditions, not inconsistent with the terms of the Plan, as the Committee shall deem appropriate:

(f) Award. A Stock Appreciation Right shall entitle the grantee, subject to such terms and conditions as the Committee may prescribe, to receive upon the exercise thereof an award equal to all or a portion of the excess of (i) the Fair Market Value of a specified number of shares of Common Stock at the time of the exercise of such right over (ii) a specified price which shall not be less than the Fair Market Value of the Common Stock at the time the right is granted or, if connected with a previously granted Stock Option, not less than the Fair Market Value of the Common Stock at the time such Stock Option was granted. Subject to the limitations set forth in Section 4, such award may be paid by the Company in cash, in shares of Common Stock (valued at their then Fair Market Value), or in any combination thereof, as the Committee may determine. Stock Appreciation Rights may be, but are not required to be, granted in connection with a previously or contemporaneously granted Stock Option.

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(g) Term. Each agreement shall state the period or periods of time within which the Stock Appreciation Right may be exercised, in whole or in part, subject to such terms and conditions prescribed for such purpose by the Committee; provided, that no Stock Appreciation Right shall be exercisable more than ten years after the date of its grant; and provided further, that each Stock Appreciation Right granted under the Plan shall become exercisable one year after the date of its grant, unless the agreement specifically provides otherwise. The Committee shall have authority to accelerate previously established exercise rights, subject to the requirements set forth in the Plan, under such circumstances and upon such terms and conditions as the Committee shall deem appropriate.

(h) Rights upon Termination of Employment. In the event that a grantee of a Stock Appreciation Right ceases to be employed either by the Company or by a Subsidiary for any reason other than such grantee’s death or Disability, any rights of the grantee under any Stock Appreciation Right then in effect immediately shall terminate; provided, that the grantee (or the grantee’s legal representative) shall have the right to exercise the Stock Appreciation Right during its term within a period of three months after such termination of employment to the extent that the Stock Appreciation Right was exercisable at the time of such termination or within such other period and subject to such other terms and conditions as may be specified by the Committee. Notwithstanding the foregoing provisions of this Section 7(c), the grantee (and the grantee’s legal representative) shall not have any rights under any Stock Appreciation Right, and the Company shall not be obligated to pay or deliver any cash, Common Stock or any combination thereof (or have any other obligation or liability) under any Stock Appreciation Right, if the Committee shall determine that (i) the employment of the grantee with the Company or any Subsidiary has been terminated for cause or (ii) the grantee has engaged or may engage in employment or activities competitive with the Company or any Subsidiary or contrary, in the opinion of the Committee, to the best interests of the Company or any Subsidiary. In the event of such determination, the grantee (and the grantee’s legal representative) shall have no right under any Stock Appreciation Right regardless of whether the grantee (or the grantee’s legal representative) shall have delivered a notice of exercise prior to the Committee’s making of such determination. Any Stock Appreciation Right may be terminated entirely by the Committee at the time of or at any time subsequent to a determination by the Committee under this Section 7(c) which has the effect of eliminating the Company’s obligations under such Stock Appreciation Right.

In the event that a grantee of a Stock Appreciation Right ceases to be employed either by the Company or by a Subsidiary by reason of such grantee’s Disability, prior to the expiration of a Stock Appreciation Right and without such grantee’s having fully exercised such Stock Appreciation Right, such grantee or such grantee’s legal representative shall have the right to exercise such Stock Appreciation Right during its

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term within a period of six months after such termination of employment to the extent that such Stock Appreciation Right was exercisable at the time of such termination or within such other period and subject to such other terms and conditions as may be specified by the Committee.

In the event that a grantee of a Stock Appreciation Right ceases to be employed either by the Company or by a Subsidiary by reason of such grantee’s death, prior to the expiration of a Stock Appreciation Right and without such grantee’s having fully exercised such Stock Appreciation Right, the personal representative of the grantee’s estate or the person who acquired the right to exercise such Stock Appreciation Right by bequest or inheritance from such grantee shall have the right to exercise such Stock Appreciation Right during its term within a period of twelve months after the date of such grantee’s death to the extent that such Stock Appreciation Right was exercisable at the time of such death or within such other period and subject to such other terms and conditions as may be specified by the Committee.

The foregoing provisions of this Section 7(c) shall not be applicable to non-employee directors of the Company.

(d) Rights Upon Termination of Service as a Director. Unless the applicable agreement provides otherwise, if a grantee of a Stock Appreciation Right who is a non-employee director of the Company ceases to be a director of the Company for any reason other than retirement from the Board under circumstances described in the following paragraph of this Section 7(d) or death, then each outstanding but unexercised Stock Appreciation Right held by such grantee shall continue to be exercisable only to the extent that it was exercisable at the time that such grantee ceased to be a director of the Company and only until the earlier of (i) three months after such grantee ceased to be a director of the Company or (ii) the expiration of the term of such Stock Appreciation Right.

Unless the applicable agreement provides otherwise, if the grantee of a Stock Appreciation Right who is a non-employee director of the Company ceases to be a director of the Company (other than by reason of death) and at the time of such occurrence (the “Retirement Date”) is at least age 65 with ten or more years of service as a director of the Company or is at least age 70 with five or more years of service as a director of the Company, then each outstanding but unexercised Stock Appreciation Right held by such grantee on the Retirement Date shall continue to be or become exercisable in accordance with its terms until the earlier of (i) five years after the Retirement Date or (ii) the expiration of the term of such Stock Appreciation Right.

Unless the applicable agreement provides otherwise, if the grantee of a Stock Appreciation Right who is a non-employee director of the Company dies, then each outstanding but unexercised Stock Appreciation Right which had been held by such grantee for at least twelve months as of the date of such grantee’s death automatically shall become exercisable in full (if not already exercisable) upon such grantee’s death. Each outstanding but unexercised Stock Appreciation Right which becomes exercisable

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pursuant to the preceding sentence and each outstanding but unexercised Stock Appreciation Right held by such grantee which was exercisable on the date of such grantee’s death may be exercised by the legal representative of such grantee’s estate or by the beneficiaries of such estate to whom such Stock Appreciation Right is distributed until the earlier of (i) three years after the date of such grantee’s death or (ii) the expiration of the term of such Stock Appreciation Right.

The foregoing provisions of this Section 7(d) shall be applicable only to non-employee directors of the Company.

8. Performance Unit Awards. Performance Unit Awards shall entitle the grantees thereof to receive future payments based upon and subject to the achievement of preestablished long-term performance targets and shall be evidenced by agreements in such form as the Committee shall approve from time to time. The agreements shall contain in substance the following terms and conditions and may contain such additional terms and conditions, not inconsistent with the terms of the Plan, as the Committee shall deem appropriate:

(i) Performance Period. The Committee shall establish with respect to each Performance Unit Award a performance period of not fewer than two years nor more than five years.

(j) Unit Value. The Committee shall establish with respect to each Performance Unit Award a value for each unit which shall not change thereafter or which may vary thereafter on the basis of criteria specified by the Committee.

(k) Performance Targets. The Committee shall establish with respect to each Performance Unit Award maximum and minimum performance targets to be achieved during the applicable performance period. The achievement of the maximum targets shall entitle a grantee to payment with respect to the full value of a Performance Unit Award. The achievement of less than the maximum targets, but in excess of the minimum targets, shall entitle a grantee to payment with respect to a portion of a Performance Unit Award according to the level of achievement of the applicable targets as specified by the Committee. To the extent the Committee deems necessary or appropriate to protect the Company against the loss of deductibility pursuant to Section 162(m) of the Code, such targets shall be established in conformity with the requirements of Section 162(m) of the Code.

(l) Performance Measures. Performance targets established by the Committee shall relate to corporate, division, subsidiary, group, or unit performance in terms of objective financial criteria or performance goals which satisfy the requirements of Section 162(m) of the Code or, with respect to grantees not subject to Section 162(m) of the Code, such other measures or standards of performance as the Committee may determine. Multiple targets may be used and may have the same or different weighting, and the targets may relate to absolute performance or relative performance measured against other companies, businesses, or indexes.

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(m) Adjustments. At any time prior to the payment of a Performance Unit Award, the Committee may adjust previously established performance targets or other terms and conditions of such Performance Unit Award, including the Company’s or another company’s financial performance for Plan purposes, in order to reduce or eliminate, but not to increase, the payment with respect to a Performance Unit Award that otherwise would be due upon the attainment of such previously established performance targets. Such adjustments shall be made to reflect major unforeseen events or changes in circumstances affecting the Company such as but not limited to changes in laws, regulations or accounting principles, mergers, acquisitions or divestitures, or other extraordinary, unusual, or nonrecurring items or events.

(n) Payment of Performance Unit Awards. Upon the conclusion of each performance period, the Committee shall determine the extent to which the applicable performance targets have been attained and any other terms and conditions have been satisfied for such period and shall provide such certification thereof as may be necessary to satisfy the requirements of Section 162(m) of the Code. The Committee shall determine what, if any, payment is due on a Performance Unit Award and, subject to the limitations set forth in Section 4, whether such payment shall be made in cash, in shares of Common Stock (valued at their then Fair Market Value), or in a combination thereof. Payment of a Performance Unit Award shall be made in a lump sum or in installments, as determined by the Committee, commencing as promptly as practicable after the end of the performance period unless such payment is deferred upon such terms and conditions as may be specified by the Committee.

(o) Termination of Employment. In the event that a grantee of a Performance Unit Award ceases to be employed either by the Company or by a Subsidiary for any reason other than such grantee’s death or Disability, any rights of such grantee under any Performance Unit Award then in effect whose performance period has not ended shall terminate immediately; provided, that the Committee may authorize the partial payment of any such Performance Unit Award if the Committee determines such action to be equitable.

In the event that a grantee of a Performance Unit Award ceases to be employed either by the Company or by a Subsidiary by reason of such grantee’s death or Disability, any rights of such grantee under any Performance Unit Award then in effect whose performance period has not ended shall terminate immediately; provided, that the Committee may authorize the payment to such grantee or such grantee’s legal representative of all or any portion of such Performance Unit Award to the extent earned under the applicable performance targets, even though the applicable performance period has not ended, upon such terms and conditions as may be specified by the Committee.

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9. Restricted Stock Awards. Restricted Stock Awards shall (i) consist of shares of Common Stock restricted against transfer, (ii) be subject to a substantial risk of forfeiture and to other terms and conditions intended to further the purpose of the Plan as the Committee may determine, and (iii) be evidenced by agreements in such form as the Committee shall approve from time to time. The agreements shall contain in substance the following terms and conditions and may contain such additional terms and conditions, not inconsistent with the terms of the Plan, as the Committee shall deem appropriate:

(p) Restriction Period. The Common Stock covered by Restricted Stock Awards shall be subject to the applicable restrictions established by the Committee over such period as the Committee shall determine. To the extent the Committee deems necessary or appropriate to protect the Company against the loss of deductibility pursuant to Section 162(m) of the Code, Restricted Stock Awards also may be subject to the attainment of one or more preestablished performance objectives which relate to corporate, subsidiary, division, group, or unit performance in terms of objective financial criteria or performance goals which satisfy the requirements of Section 162(m) of the Code; provided, that any such preestablished financial criteria or performance goals subsequently may be adjusted by the Committee to reduce or eliminate, but not to increase, a Restricted Stock Award in order to take into account unforeseen events or changes in circumstances affecting the Company such as but not limited to changes in laws, regulations or accounting principles, mergers, acquisitions or divestitures, or other extraordinary, unusual, or nonrecurring items or events.

(q) Restriction upon Transfer. Shares of Common Stock covered by Restricted Stock Awards may not be sold, assigned, transferred, exchanged, pledged, hypothecated, or otherwise encumbered, except as provided in the Plan or in any Restricted Stock Award agreement entered into between the Company and a grantee, during the restriction period applicable to such shares. Notwithstanding the foregoing provisions of this Section 9(b), and except as otherwise provided in the Plan or the applicable Restricted Stock Award agreement, a grantee of a Restricted Stock Award shall have all of the other rights of a holder of Common Stock including but not limited to the right to receive dividends and the right to vote such shares.

(r) Payment. The Committee shall determine the amount, form and time of payment, if any, that shall be required from the grantee of a Restricted Stock Award in consideration of the issuance and delivery of the shares of Common Stock covered by such Restricted Stock Award.

(s) Certificates. Each certificate issued in respect of shares of Common Stock covered by a Restricted Stock Award shall be registered in the name of the grantee and shall bear substantially the following legend (in addition to any other legends which may be appropriate):

“This certificate and the shares of stock represented hereby are subject to the terms and conditions (including forfeiture provisions and restrictions against transfer) contained in the CSG Systems International, Inc. 2005 Stock Incentive Plan and a Restricted Stock Award Agreement entered into between the registered owner and CSG Systems International, Inc. Release from such terms and conditions may be obtained only in accordance with the provisions of such Plan and Agreement, a copy of each of which is on file in the office of the Secretary of CSG Systems International, Inc.”

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The Committee may require the grantee of a Restricted Stock Award to enter into an escrow agreement providing that the certificates representing the shares covered by such Restricted Stock Award will remain in the physical custody of an escrow agent until all restrictions are removed or expire and may require that the certificates held in such escrow be accompanied by a stock power, endorsed in blank by the grantee, relating to the Common Stock covered by such certificates. The Company also may use a book-entry system of uncertificated shares to administer grants of Restricted Stock Awards and to effect any withholding required by Section 15.

(t) Lapse of Restrictions. Except for preestablished performance objectives established with respect to Restricted Stock Awards to grantees subject to Section 162(m) of the Code, the Committee may provide for the lapse of restrictions applicable to Common Stock subject to Restricted Stock Awards in installments and may waive such restrictions in whole or in part based upon such factors and such circumstances as the Committee shall determine. Upon the lapse of such restrictions, subject to the provisions of Section 15, certificates for shares of Common Stock, free of the restrictive legend set forth in Section 9(d), shall be issued to the grantee or the grantee’s legal representative automatically in the case of certificated shares or upon the request of the grantee in the case of uncertificated shares. The Committee shall have authority to accelerate the expiration of the applicable restriction period with respect to all or any portion of the shares of Common Stock covered by a Restricted Stock Award except, with respect to grantees subject to Section 162(m) of the Code, to the extent such acceleration would result in the loss of the deductibility of such Restricted Stock Award pursuant to Section 162(m) of the Code.

(u) Termination of Employment or Service as a Director. If a grantee of a Restricted Stock Award ceases to be employed either by the Company or by a Subsidiary or to serve as a director of the Company for any reason, then any rights of such grantee with respect to shares of Common Stock that remain subject to restrictions under such Restricted Stock Award shall terminate immediately, and any shares of Common Stock covered by a Restricted Stock Award with unlapsed restrictions shall be subject to reacquisition by the Company upon the terms set forth in the applicable agreement with such grantee. The Committee may provide for complete or partial exceptions to such employment or service requirement if the Committee determines such action to be equitable.

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10. Restricted Stock Unit Awards. Restricted Stock Unit Awards shall entitle the grantees thereof to receive future payments from the Company either in shares of Common Stock or in cash or in a combination of Common Stock and cash at such time or times and on such terms as the Committee shall approve from time to time. The following provisions shall be applicable to Restricted Stock Unit Awards:

(a) Award Agreement. Each Restricted Stock Unit Award shall be evidenced by an agreement, in a form approved by the Committee, which sets forth the number of Restricted Stock Units covered by such Award, the time or times when such Restricted Stock Units will vest in the grantee, and such other terms and conditions, not inconsistent with the terms of the Plan, as the Committee shall deem appropriate.

(b) Payment of Award. Upon the vesting of a Restricted Stock Unit, the Company shall pay the amount of such Restricted Stock Units to the grantee either (i) in shares of Common Stock on the basis of one share of Common Stock for each vested Restricted Stock Unit, (ii) in cash in an amount equal to the Fair Market Value on the vesting date of one share of Common Stock for each vested Restricted Stock Unit, or (iii) in a combination of cash and shares of Common Stock as the Committee in its discretion shall determine with respect to such Award either in the applicable Award agreement or at the time of the vesting of such Restricted Stock Unit.

(c) Termination of Employment or Service as a Director. If a grantee of a Restricted Stock Unit Award ceases to be employed either by the Company or by a Subsidiary or to serve as a director of the Company for any reason, then any rights of such grantee with respect to the unvested portion of such Restricted Stock Unit Award shall terminate immediately. The Committee may provide for complete or partial exceptions to such employment or service requirement if the Committee determines such action to be equitable.

(d) Performance Objectives. To the extent the Committee deems necessary or appropriate to protect the Company against the loss of deductibility pursuant to Section 162(m) of the Code, Restricted Stock Unit Awards may be subject to the attainment of one or more preestablished performance objectives which relate to corporate, subsidiary, division, group, or unit performance in terms of objective financial criteria or performance goals which satisfy the requirements of Section 162(m) of the Code; provided, that any such preestablished financial criteria or performance goals subsequently may be adjusted by the Committee to reduce or eliminate, but not to increase, a Restricted Stock Unit Award in order to take into account unforeseen events or changes in circumstances affecting the Company such as but not limited to changes in laws, regulations or accounting principles, mergers, acquisitions or divestitures, or other extraordinary, unusual, or nonrecurring items or events.

11. Stock Bonus Awards. The Committee may grant a Stock Bonus Award to an eligible grantee under the Plan based upon corporate, division, subsidiary, group, or unit performance in terms of preestablished objective financial criteria or performance goals or, with respect to participants not subject to Section 162(m) of the Code, such other measures or standards of performance (including but not limited to performance already accomplished) as the Committee may determine; provided, that any such preestablished financial criteria or performance goals subsequently may be adjusted to reduce or eliminate, but not to increase, a Stock Bonus Award in order to take into account unforeseen events or changes in circumstances affecting the Company such as but not limited to changes in laws, regulations or accounting principles, mergers, acquisitions or divestitures, or other extraordinary, unusual, or nonrecurring items or events.

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If appropriate in the sole discretion of the Committee, Stock Bonus Awards shall be evidenced by agreements in such form as the Committee shall approve from time to time. In addition to any applicable performance goals or standards and subject to the terms of the Plan, shares of Common Stock which are the subject of a Stock Bonus Award may be (i) subject to additional restrictions (including but not limited to restrictions on transfer) or (ii) granted directly to a grantee free of any restrictions, as the Committee shall deem appropriate.

12. General Restrictions. Each award or grant under the Plan shall be subject to the requirement that if at any time the Committee shall determine that (i) the listing, registration, or qualification of the shares of Common Stock subject or related thereto upon any securities exchange or under any state or federal law, (ii) the consent or approval of any governmental regulatory body, or (iii) an agreement by the grantee of an award or grant with respect to the disposition of the shares of Common Stock subject or related thereto is necessary or desirable as a condition of, or in connection with, such award or grant or the issuance or purchase of shares of Common Stock thereunder, then such award or grant may not be consummated and any rights thereunder may not be exercised in whole or in part unless such listing, registration, qualification, consent, approval, or agreement shall have been effected or obtained upon conditions acceptable to the Committee. Awards or grants under the Plan shall be subject to such additional terms and conditions, not inconsistent with the Plan, as the Committee in its sole discretion deems necessary or desirable, including but not limited to such terms and conditions as are necessary to enable a grantee to avoid any short-swing profit recapture liability under Section 16 of the Exchange Act.

13. Single or Multiple Agreements. Multiple forms of awards or grants or combinations thereof may be evidenced either by a single agreement or by multiple agreements, as determined by the Committee.

14. Rights of a Stockholder. Unless otherwise provided by the Plan, the grantee of any award or grant under the Plan shall have no rights as a stockholder of the Company with respect to the shares of Common Stock subject or related to such award or grant unless and until certificates for such shares of Common Stock are issued to such grantee or until uncertificated shares have been credited to an account established for such grantee.

15. No Right to Continue Employment or Service as a Director. Nothing in the Plan or in any agreement entered into pursuant to the Plan shall confer upon any grantee who is an employee of the Company or any Subsidiary the right to continue in the employment of the Company or any Subsidiary or affect any right which the Company or any Subsidiary may have to terminate the employment of such grantee with or without cause. Nothing in the Plan or in any agreement entered into pursuant to the Plan shall confer upon any grantee who is a non-employee director of the Company the right to continue to serve as a director of the Company.

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16. Withholding. The Company’s obligation to (i) deliver shares of Common Stock or pay cash upon the exercise of any Stock Option or Stock Appreciation Right, (ii) deliver shares of Common Stock or pay cash in payment of any Performance Unit Award, (iii) deliver stock certificates upon the vesting of any Restricted Stock Award, (iv) deliver shares of Common Stock or pay cash upon the vesting of any Restricted Stock Unit Award, or (v) deliver shares of Common Stock upon the grant of any Stock Bonus Award shall be subject to applicable federal, state, and local tax withholding requirements. In the discretion of the Committee, amounts required to be withheld for taxes may or must be paid by the grantee in cash or shares of Common Stock (either through the surrender of previously held shares of Common Stock or the withholding of shares of Common Stock otherwise issuable or deliverable upon the exercise, payment or vesting of such Stock Option, Stock Appreciation Right, or Award) having a Fair Market Value equal to the required tax withholding amount and upon such other terms and conditions as the Committee shall determine; provided, that any election by a grantee subject to Section 16(b) of the Exchange Act to pay any tax withholding in shares of Common Stock shall be subject to and must comply with any applicable rules under Section 16(b) of the Exchange Act.

17. Indemnification. No member of the Board or the Committee, and no officer or employee of the Company or a Subsidiary acting on behalf of the Board or the Committee, shall be personally liable for any action, determination, or interpretation taken or made in good faith with respect to the Plan or any award or option granted under the Plan; and all members of the Board or the Committee and each and any officer or employee of the Company or any Subsidiary acting on their behalf shall, to the fullest extent permitted by law, be fully indemnified and held harmless by the Company in respect of any such action, determination or interpretation.

18. Non-Assignability. No award or grant under the Plan shall be assignable or transferable by the recipient thereof except by will, by the laws of descent and distribution, or, in the case of awards or grants other than Incentive Stock Options, pursuant to a qualified domestic relations order. No right or benefit under the Plan shall be liable for the debts, liabilities, or alimony or child support obligations of the person entitled to such right or benefit, either by assignment, attachment, or any other method, and shall not be subject to be taken by the creditors or alimony or child support obligees of the person entitled to such right or benefit by any process whatsoever.

19. Nonuniform Determinations. The Committee’s determinations under the Plan (including but not limited to determinations of the persons to receive awards or grants, the form, amount, and timing of such awards or grants, the terms and provisions of such awards or grants and the agreements evidencing them, and the establishment of values and performance targets) need not be uniform and may be made by the Committee selectively among the persons who receive, or are eligible to receive, awards or grants under the Plan, whether or not such persons are similarly situated.

20. Adjustments. In the event of any change in the outstanding shares of Common Stock, by reason of a stock dividend or distribution, stock split, recapitalization, merger, reorganization, consolidation, split-up, spin-off, combination of shares, exchange of shares, or other change in corporate structure affecting the Common Stock, the Committee shall make appropriate adjustments in (a) the aggregate number of shares of Common Stock (i) reserved for issuance under the Plan, (ii) for which grants or awards may be made to an individual grantee,

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and (iii) covered by outstanding awards and grants denominated in shares or units of Common Stock, (b) the exercise or other applicable price related to outstanding awards or grants, and (c) the appropriate Fair Market Value and other price determinations relevant to outstanding awards or grants and shall make such other adjustments not inconsistent with the provisions of Section 22 as may be equitable under the circumstances; provided, that the number of shares subject to any award or grant always shall be a whole number.

21. Terms of Payment. Subject to any other applicable provisions of the Plan and to any applicable laws, whenever payment by a grantee is required with respect to shares of Common Stock which are the subject of an award or grant under the Plan, the Committee shall determine the time, form, and manner of such payment, including but not limited to lump-sum payments and installment payments upon such terms and conditions as the Committee may prescribe. Installment payment obligations of a grantee may be evidenced by full-recourse, limited-recourse, or non-recourse promissory notes or other instruments, with or without interest and with or without collateral or other security as the Committee may determine.

22. Termination and Amendment. The Board may terminate the Plan or amend the Plan or any provision thereof at any time, including but not limited to amendments to the Plan necessary to comply with the requirements of Section 16(b) of the Exchange Act, Section 162(m) of the Code, Section 422 of the Code, or regulations issued under any of such statutory provisions. The termination or any amendment of the Plan shall not, without the consent of a grantee, adversely affect such grantee’s rights under an award or grant previously made to such grantee under the Plan. The Committee may amend the terms of any award or grant previously made under the Plan, prospectively or retroactively; but, subject to the provisions of Section 20, no such amendment shall, except as otherwise expressly permitted by the Plan, adversely affect the rights of the grantee of such award or grant without such grantee’s consent. Except in connection with a transaction involving the Common Stock (such as but not limited to a stock dividend, stock split, extraordinary cash dividend, recapitalization, reorganization, merger, consolidation, split-up, spin-off, combination of shares, or exchange of shares), the Committee may not, without stockholder approval, (i) amend the terms of an outstanding Stock Option so as to reduce the exercise price of such Stock Option, (ii) amend the terms of a Stock Appreciation Right so as to reduce the specified stock price applicable to such Stock Appreciation Right at the time of its grant, or (iii) cancel an outstanding Stock Option or Stock Appreciation Right in exchange for cash, other awards, Stock Options with an exercise price that is less than the exercise price of the original Stock Option, or Stock Appreciation Rights with a specified stock price that is less than the specified stock price applicable to the original Stock Appreciation Right. Notwithstanding the foregoing provisions of this Section 22, stockholder approval of any action referred to in this Section 22 shall be required whenever necessary to satisfy the applicable requirements of Section 16(b) of the Exchange Act, Section 162(m) of the Code, Section 422 of the Code, or any regulations issued under any of such statutory provisions or the applicable requirements of any market or exchange on which shares of the Common Stock are listed or traded.

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23. Severability. With respect to participants subject to Section 16 of the Exchange Act, (i) the Plan is intended to comply with all applicable conditions of Rule 16b-3 or any successor to such rule, (ii) all transactions involving grantees who are subject to Section 16(b) of the Exchange Act are subject to such conditions, regardless of whether the conditions are expressly set forth in the Plan, and (iii) any provision of the Plan that is contrary to a condition of Rule 16b-3 shall not apply to grantees who are subject to Section 16(b) of the Exchange Act. If any of the terms or provisions of the Plan, or awards or grants made under the Plan, conflict with the requirements of Section 162(m) or Section 422 of the Code with respect to awards or grants intended to be subject to or governed by Section 162(m) or Section 422 of the Code, as the case may be, then such terms or provisions shall be deemed to be inoperative to the extent they so conflict with the requirements of Section 162(m) or Section 422 of the Code, as the case may be. With respect to an Incentive Stock Option, if the Plan does not contain any provision required to be included in the Plan under Section 422 of the Code (as amended from time to time) or any successor to such section, then such provision shall be deemed to be incorporated in the Plan with the same force and effect as if such provision had been expressly set out in the Plan.

24. Effect on Other Plans. Participation in the Plan shall not affect the eligibility of an employee or a non-employee director of the Company to participate in any other benefit or incentive plan of the Company or any Subsidiary. Any awards made pursuant to the Plan shall not be taken into account in determining the benefits provided or to be provided under any other plan of the Company or any Subsidiary unless otherwise specifically provided in such other plan.

25. Term of Plan. The Plan shall become effective on the date of its approval by the stockholders of the Company and shall terminate for purposes of further grants on the first to occur of (i) December 31, 2020, or (ii) the effective date of the termination of the Plan by the Board pursuant to Section 22. No awards or options may be granted under the Plan after the termination of the Plan, but such termination shall not affect any awards or options outstanding under the Plan at the time of such termination or the authority of the Committee to continue to administer the Plan apart from the making of further grants.

26. Governing Law. The Plan shall be governed by and construed in accordance with the laws of Delaware.

27. Section 409A.

(a) Time and Form of Payment. Notwithstanding anything contained in the Plan or in an award agreement to the contrary, the time and form of payment of an award that is subject to the limitations imposed by Section 409A of the Code shall be set forth in the applicable award agreement on or before the time at which the grantee of the award obtains a legally binding right to the award (or such other time permitted under Section 409A of the Code) and such time and form of payment shall comply with the requirements of Section 409A of the Code.

(b) Delay in Payment. Notwithstanding anything contained in the Plan or an award agreement to the contrary, if the grantee of the award is deemed by the Company at the time of such grantee’s “separation from service” with the Company to be a “specified employee” as determined under Section 409A of the Code, any nonqualified deferred compensation to which such grantee is entitled under the Plan in connection with such separation from service shall not be paid or commence payment until the date

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which is the first business day following the six-month period after such grantee’s separation from service (or if earlier, such grantee’s death). Such delay in payment shall only be effected with respect to each separate payment to the extent required to avoid adverse tax treatment to such grantee under Section 409A of the Code. Any compensation which would have otherwise been paid during the delay period (whether in a lump sum or in installments) in the absence of this Section 27 shall be paid to such grantee or such grantee’s Beneficiary in a lump-sum payment on the first business day following the expiration of the delay period.

(c) Amendments. Notwithstanding anything in the Plan to the contrary, the Plan and awards granted under the Plan are intended to be eligible for certain regulatory exceptions to the limitations of, or to comply with, the requirements of Section 409A of the Code. The Committee, in the exercise of its sole discretion and without the consent of the grantee of an award under the Plan, may amend or modify the terms of an award in any manner and delay the payment of any amounts payable pursuant to an award to the minimum extent necessary to reasonably comply with the requirements of Section 409A of the Code, provided that the Company shall not be required to assume any increased economic burden. No action so taken by the Committee with respect to the requirements of Section 409A of the Code shall be deemed to adversely affect the rights of a grantee of an award under the Plan with respect to an award or to require the consent of such grantee. The Committee reserves the right to make additional changes to the Plan and awards from time to time to the extent it deems necessary with respect to Section 409A of the Code.

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EX-10.05

Exhibit 10.05

[As amended

August 14, 2007]

CSG SYSTEMS INTERNATIONAL, INC.

PERFORMANCE BONUS PROGRAM

1. Purpose.

The purpose of the CSG Systems International, Inc. Performance Bonus Program (the “Program”) is to provide for annual cash bonus awards (a “Bonus Award”) under the Program for (i) the persons designated as executive officers of CSG Systems International, Inc. (the “Company”) by the Board of Directors of the Company and (ii) any other employee of the Company or its subsidiaries who is or may be a “covered employee” of the Company or its subsidiaries as defined in Section 162(m)(3) of the Internal Revenue Code of 1986, as amended (the “Code”), that constitute performance-based compensation within the meaning of Section 162(m)(4)(C) of the Code and Treasury Regulations § 1.162-27. For purposes of the Program, “Participant” means a person referred to in the first sentence of this Section 1. Bonus Awards under the Program shall be paid for services performed by a Participant during a calendar year.

2. Administration.

(a) The Program shall be administered by the Compensation Committee (the “Committee”) of the Company’s Board of Directors (the “Board”). No member of the Committee shall be eligible to participate in the Program. The Committee at all times shall be comprised of two or more members who are “outside directors” for purposes of Section 162(m)(4)(C)(i) of the Code.

(b) The Committee shall have the power and discretionary authority to adopt, amend, and rescind any rules, regulations, and procedures which the Committee deems necessary or appropriate for the operation and administration of the Program and to interpret and rule on any questions relating to any provision of the Program. However, the Committee shall not take any action that would result in the payment of compensation under the Program to any Participant who is a “covered employee” as defined in Section 162(m)(3) of the Code if such payment would not be “performance-based compensation” within the meaning of Section 162(m) of the Code, as reasonably determined by the Committee.

(c) The decisions of the Committee (including but not limited to decisions as to whether a Participant is entitled to payment of a Bonus Award in whole or in part or not at all) shall be final, conclusive, and binding on all parties, including the Company and each Participant.

(d) The Board from time to time may amend, suspend, or terminate the Program, in whole or in part; provided, that no payment which becomes due under the Program as a result of an amendment of the Program that requires stockholder approval to satisfy the requirements of Section 162(m) of the Code shall be made until the Company has obtained such stockholder approval.

3. Performance Goals.

(a) Not later than ninety (90) days after the beginning of each calendar year, the Committee shall establish in writing (i) one or more Performance Goals (as defined in Section 3(c)) that must be attained in order for a Participant to receive a Bonus Award for such calendar year and (ii) the method, in terms of an objective formula or standard, for computing the amount of the Bonus Award to be paid to a Participant if the applicable Performance Goals are attained. Subject to and consistent with the provisions of the preceding sentence, the Committee shall determine the potential Bonus Award which a Participant shall be eligible to receive for a particular calendar year and may establish terms and conditions in addition to (but not in lieu of) the attainment of Performance Goals that a Participant must satisfy in order to receive such Bonus Award. Actual and potential Bonus Awards and such additional terms and conditions need not be uniform among Participants. The Committee shall have the discretion to revise the amount of a Bonus Award payable to a Participant upon the attainment of Performance Goals solely for the purpose of reducing the amount of or eliminating such Bonus Award. A Participant’s level of satisfaction of any additional terms and conditions established by the Committee for such Participant’s receipt of a Bonus Award shall be relevant only for the purpose of potentially reducing the amount of or eliminating such Participant’s Bonus Award and may not be used to increase such Participant’s Bonus Award beyond that which would be payable based solely upon the Company’s attainment of applicable Performance Goals.

(b) The maximum individual Bonus Award payable to a Participant for any calendar year shall be equal to 200% of the annual base salary of such Participant as of the last day of such calendar year; provided, however, that in no event may a Participant’s maximum Bonus Award under the Program for any calendar year exceed $3,000,000 or such lesser amount as is established by the Committee for such calendar year.

(c) A “Performance Goal” is an objective performance goal based entirely on one or more of the following business criteria applicable to the Company: net income, adjusted net income, operating income, adjusted operating income, revenue, adjusted revenue, earnings, adjusted earnings, gross margin, return on stockholders’ equity, stock price, earnings per share, adjusted earnings per share, and cash flow. Except as provided in Section 3(d), Performance Goals for a calendar year may not be changed once established by the Committee; however, the Committee retains discretion to reduce or eliminate a Participant’s Bonus Award as provided in Section 3(a). Performance Goals may be particular to an individual Participant or to a subsidiary or other business unit of the Company or may be based upon the performance of the Company and its subsidiaries as a whole. Performance Goals may vary from Participant to Participant and from calendar year to calendar year.

(d) If, after the Committee has established a Performance Goal for a particular calendar year, the Company or any of its subsidiaries (i) acquires or disposes of any assets, business division, subsidiary, or other business operations, (ii) discontinues any business operations, or (iii) incurs any restructuring charge or any item of extraordinary loss or expense (each event in the preceding clauses (i), (ii), and (iii) being referred to as a “Subsequent Event”) and such Subsequent Event has a materially positive or negative effect upon the attainment of such Performance Goal as originally established, then the Committee shall adjust such original Performance Goal so that such Performance Goal as adjusted is comparable to what such Performance Goal would have been had the Committee taken such Subsequent Event into account when the Committee originally established such Performance Goal.

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(e) Notwithstanding any other provision of the Program, the Committee shall have the discretion to pay a Bonus Award to a Participant regardless of the attainment of a Performance Goal in the event of such Participant’s death or termination of employment on account of a long-term disability as determined by the Committee.

4. Communication.

The Committee promptly shall inform each Participant in writing of the Performance Goals applicable to such Participant for a particular calendar year and (subject to the provisions of the Program) the terms and conditions of such Participant’s participation in the Program for such calendar year.

5. Certification.

Prior to the payment of any Bonus Award, the Committee shall certify in writing that the applicable Performance Goals have been attained. No payment shall be made under the Program in the absence of such certification; however, the attainment or failure to attain Performance Goals under the Program shall not preclude the payment of compensation, including discretionary payments, to a Participant under any other plan, program, agreement, or arrangement of the Company or its subsidiaries, whether now existing or established after the adoption of the Program, on the basis of goals or criteria separate from the business criteria set forth in Section 3(c) or pursuant to the terms of such other plan, program, agreement, or arrangement.

6. Payment of Bonus Awards.

The Company shall pay the Bonus Awards for a calendar year in cash as soon as practicable after the certification of the attainment of the Performance Goals pursuant to Section 5 and the final determination of the amount of each Bonus Award to be paid; provided, that, so long as such certification and determination have occurred, the Company shall pay the Bonus Awards for a calendar year not later than March 15 of the following calendar year; and provided further, that payment of part or all of any Bonus Award shall be deferred by the Company in accordance with the terms of any separate deferred compensation agreement or arrangement applicable to a Participant. As a further condition of the payment of a Participant’s Bonus Award for a particular calendar year, such Participant must be employed by the Company or its subsidiaries on the last day of such calendar year. The Committee may provide, as a further condition of the payment of a Participant’s Bonus Award for a particular calendar year, that the Participant must be employed by the Company or its subsidiaries on the date of the Committee’s certification of the Company’s attainment of the Performance Goals for such calendar year or on any other date subsequent to the last day of such calendar year. Notwithstanding the foregoing, to the extent the payment of the Bonus Award is not subject to any separate deferred compensation agreement, the Bonus Award shall be paid in a cash lump-sum payment made during the calendar year immediately following the calendar year to which the Bonus Award relates (or such other time permitted under Section 409A of the Code).

7. Effective Date of Program.

The Program shall be effective January 1, 2007, subject to approval by the holders of a majority of the shares of common stock of the Company present or represented by proxy at the 2007 annual meeting of stockholders of the Company. No payment shall be made under the

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Program unless the stockholders of the Company have approved the Program as required by Section 162(m) of the Code and Treasury Regulations § 1.162-27 prior to such payment. The Program shall continue until terminated by the Board but shall be resubmitted to stockholders from time to time as required by Section 162(m) of the Code and Treasury Regulations § 1.162-27.

8. Miscellaneous.

(a) Participants in the Program are unsecured general creditors of the Company, with no secured or preferential right to any assets of the Company or any other entity for payment of Bonus Awards under the Program.

(b) A Participant shall have no right to commute, sell, assign, transfer, pledge, anticipate, mortgage, or otherwise encumber, transfer, hypothecate, or convey in advance of actual receipt the amounts, if any, payable to such Participant under the Program. No part of any amounts payable to a Participant under the Program shall, prior to actual payment, be subject to seizure or sequestration for the payment of any debt, judgment, alimony, or separate maintenance owed by such Participant or any other person or be transferable by operation of law in the event of a Participant’s or any other person’s bankruptcy or insolvency.

(c) The Program does not constitute a contract of employment between the Company or any of its subsidiaries and any Participant and does not entitle any Participant to continued employment with the Company or any of its subsidiaries.

(d) The Company and its subsidiaries shall have the right to deduct from all amounts payable to a Participant under the Program any taxes required by law or other amounts authorized by the Participant to be withheld from payments under the Program.

(e) The Company and its subsidiaries reserve the right from time to time to establish, implement, and modify compensation plans, programs, agreements, and arrangements other than and in addition to the Program for persons who are Participants in the Program.

(f) The Program shall be construed and interpreted according to the laws of the State of Delaware, except as preempted by federal law, and without regard to conflict of law principles.

9. Section 409A.

Notwithstanding anything in the Program to the contrary, the Program and Bonus Awards made under the Program are intended to be eligible for certain regulatory exceptions to the limitations of, or to comply with, the requirements of Section 409A of the Code. The Committee, in the exercise of its sole discretion and without the consent of the Participant, may amend or modify a Bonus Award in any manner and delay the payment of any amounts payable pursuant to a Bonus Award to the minimum extent necessary to reasonably comply with the requirements of Section 409A of the Code; provided, that the Company shall not be required to assume any increased economic burden. No action so taken by the Committee with respect to the requirements of Section 409A of the Code shall be deemed to adversely affect a Participant’s right with respect to a Bonus Award or to require the consent of such Participant. The Committee shall have the right to make additional changes to Bonus Awards from time to time to the extent it deems necessary with respect to Section 409A of the Code.

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