Exhibit (m)(1)

               FORM OF DISTRIBUTION AND SHAREHOLDER SERVICING PLAN
                              JANUS INVESTMENT FUND
                                 CLASS A SHARES

      WHEREAS, Janus Investment Fund (the "Trust") engages in business as an
open-end management investment company and is registered as such under the
Investment Company Act of 1940, as amended (the "Act");

      WHEREAS, shares of beneficial interest of the Trust are currently divided
into multiple series ("Funds"), each with multiple classes of shares (and
additional classes may be added in the future), one of which is designated the
"Class A Shares";

      WHEREAS, Janus Distributors LLC ("JD" or "Distributor") serves as the
distributor of Class A Shares pursuant to an Amended and Restated Distribution
Agreement dated July 6, 2009, as amended from time to time, between Distributor
and the Trust; and

      NOW, THEREFORE, the Trust hereby adopts with respect to the Class A Shares
of each Fund, and the Distributor hereby agrees to the terms of, the Plan, in
accordance with Rule 12b-1 under the Act on the following terms and conditions:

      1. The Trust shall pay to the Distributor, as the distributor of the Class
A Shares, a fee for distribution and/or servicing of the shares at the rate of
up to 0.25% on an annualized basis of the average daily net assets of the Class
A Shares, provided that, at any time such payment is made, whether or not this
Plan continues in effect, the making thereof will not exceed any applicable
restriction imposed by rules of the Financial Industry Regulatory Authority
("FINRA"). Such fee shall be calculated and accrued daily and paid on the first
business day of each calendar month for the preceding month or at such other
intervals as the Trustees shall determine.

      2. The amount set forth in paragraph 1 of this Plan shall be paid for the
Distributor's services as distributor of Class A Shares in connection with any
activities or expenses primarily intended to result in the sale and/or servicing
of the Class A Shares, including, but not limited to, payment of compensation,
including incentive compensation, to securities dealers and other financial
institutions and organizations (collectively, the "Service Providers") to obtain
various distribution related and/or administrative services for the investors in
the Class A Shares. These services may include, but are not limited to the
following functions: printing and delivering prospectuses, statements of
additional information, shareholder reports, proxy statements and marketing
materials related to Class A Shares to prospective and existing investors;
providing educational materials regarding Class A Shares; providing facilities
to answer questions from prospective and/or existing investors about the Funds;
receiving and answering correspondence; complying with federal and state
securities laws pertaining to the sale of Class A Shares; assisting investors in
completing application forms and selecting dividend and other accounts options
and any other activities for which "service fees" may be paid under Rule 2830 of
the National Association of Securities Dealers, Inc. ("NASD"). The Distributor
is also authorized to engage directly in any activities relating to the purposes
of this Plan. Payments under the Plan are not tied exclusively to actual
distribution and service expenses, and the payments may exceed distribution and
service expenses actually incurred. The

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Distributor may retain some or all fees payable under the Plan in certain
circumstances, including when there is no Service Provider of record or when
qualification standards have not been met by the Service Provider of record.

      3. This Plan shall not take effect until it, together with any related
agreements, has been approved by votes of a majority of both (a) the Trustees of
the Trust and (b) those Trustees of the Trust who are not "interested persons"
of the Trust (as defined in the Act) and who have no direct or indirect
financial interest in the operation of this Plan or any agreements related to it
(the "Rule 12b-1 Trustees"), cast in person at a meeting (or meetings) called
for the purpose of voting on this Plan and such related agreements.

      4. After approval as set forth in paragraph 3, this Plan shall take effect
as of the date of execution. The Plan shall continue in full force and effect as
to the Class A Shares of each Fund for so long as such continuance is
specifically approved at least annually in the manner provided for approval of
this Plan in paragraph 3.

      5. The Distributor shall provide to the Trustees of the Trust, and the
Trustees shall review, at least quarterly, a written report of the amounts so
expended and the purposes for which such expenditures were made.

      6. This Plan may be terminated as to the Class A Shares of any Fund at any
time, without payment of any penalty, (a) by vote of a majority of the Rule
12b-1 Trustees or (b) by a vote of a majority of the outstanding voting
securities (as defined in the Act) of the Class A Shares of the Fund.

      7. This Plan may not be amended to increase materially the amount of the
fee provided for in paragraph 1 hereof for any Fund unless such amendment is
approved by a vote of a majority of the outstanding voting securities (as
defined in the Act) of the Class A Shares of that Fund and no material amendment
to the Plan shall be made unless approved in the manner provided for approval
and annual renewal in paragraph 3 hereof.

      8. While this Plan is in effect, at least 75% of the Trustees must not be
"interested persons" (as defined in the Act) of the Trust and the selection and
nomination of Trustees who are not "interested persons" (as defined in the Act)
of the Trust shall be committed to the discretion of the Trustees who are not
such interested persons.

      9. The Trust shall preserve copies of this Plan and any related agreements
and all reports made pursuant to paragraph 5 hereof, for a period of not less
than six years from the date of this Plan, any such agreement or any such
report, as the case may be, the first two years in an easily accessible place.

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      IN WITNESS WHEREOF, the Trust, on behalf of the Class A Shares of each
Fund, and the Distributor have executed this Distribution Plan as of the 6th day
of July, 2009.

                                            JANUS INVESTMENT FUND

                                            By:
                                                --------------------------------
                                            Name: Stephanie Grauerholz-Lofton
                                            Title: Vice President, Chief Legal
                                                   Counsel and Secretary

                                            JANUS DISTRIBUTORS LLC

                                            By:
                                                --------------------------------
                                            Name: Heidi W. Hardin
                                            Title: Senior Vice President,
                                                   General Counsel and Secretary

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