10-K/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington DC 20549

Form 10-K/A

Amendment No. 1

ýANNUAL REPORT PURSUANT TO SECTION 13 or 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2004

OR

oTRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF
THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from                        to

Commission file number 0-23067

CONCORD COMMUNICATIONS, INC.

(Exact name of registrant as specified in its charter)

Massachusetts	04-2710876
(State of incorporation)	(IRS Employer Identification Number)

600 Nickerson Road

Marlborough, Massachusetts 01752

(508) 460-4646

(Address and telephone number of principal executive offices)

Securities registered pursuant to Section 12(b) of the Act:     None

Securities registered pursuant to Section 12(g) of the Act:

Common Stock, par value $0.01 per share

(Title of class)

        Indicate by check mark whether the registrant (1) has filed all reports required to be filed by section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.     Yes ý          No o

        Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K     o

        Indicate by check mark whether the registrant is an accelerated filer (as defined in Exchange Act Rule 12b-2):     Yes ý          No o

        The aggregate market value of the voting stock held by non-affiliates of the Registrant, based on the closing sale price of the registrant’s common stock on June 30, 2004, as reported on the NASDAQ National Market was approximately $208,801,000

        The number of shares outstanding of Common Stock as of May 10, 2005 was 18,858,849.

EXPLANATORY NOTE:     Concord Communications, Inc. (the “Company”) is filing this Amendment No. 1 to its Form 10-K for the year ended December 31, 2004, as filed on March 16, 2005 (the “Original Filing”)  to correct an inadvertent error in Section 4 of the certifications filed as Exhibits 31.1 and 31.2 to the Form 10-K.  There are no other changes to these certifications or to the Form 10-K.

Because no financial statements are being filed with this Amendment No. 1, the Company is not including certifications pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.  Except as described herein, this Amendment No. 1 on Form 10-K/A does not modify or update other disclosures in, or exhibits to, the Original Filing.

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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 thereunto duly authorized this 13th day of May 2005.

CONCORD COMMUNICATIONS, INC.
/s/ MELISSA H. CRUZ
Name: Melissa H. Cruz
Title:	Executive Vice President, Business Services Chief Financial Officer and Treasurer (Principal Financial and Accounting Officer)

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EXHIBIT INDEX

Exhibit Number	Description
31.1	Certification of Principal Executive Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002
31.2	Certification of Principal Financial Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002

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EX-31.1

EXHIBIT 31.1

CERTIFICATIONS

I, John A. Blaeser, certify that:

      1. I have reviewed this annual report on Form 10-K of Concord Communications, Inc.;

  
60;   2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

      3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

      4. The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13(a) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15a-15(f)) for the registrant and we have:

             a. Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, p articularly during the period in which this report is being prepared;

             b. Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

           & #160; c.  Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

             d. Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

      5. The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

             a. All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant ’s ability to record, process, summarize and report financial information; and

             b. Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal controls over financial reporting.

/s/ JOHN A. BLAESER

John A. Blaeser

President and Chief Executive Officer

May 13, 2005

EX-31.2

EXHIBIT 31.2

CERTIFICATIONS

I, Melissa H. Cruz, certify that:

      1. I have reviewed this annual report on Form 10-K of Concord Communications, Inc.;

  
60;   2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

      3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

      4. The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13(a) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15a-15(f)) for the registrant and we have:

             a. Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, p articularly during the period in which this report is being prepared;

             b. Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

           & #160; c. Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

             d. Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

      5. The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

             a. All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’ s ability to record, process, summarize and report financial information; and

             b. Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal controls over financial reporting.

/s/ MELISSA H. CRUZ

Melissa H. Cruz

Executive Vice President Business Services

Chief Financial Officer and Treasurer

May 13, 2005