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                                                                   Exhibit 4 (u)

                             SUB-ADVISORY AGREEMENT

                        JANUS ADVISER MID CAP VALUE FUND
                       (A SERIES OF JANUS ADVISER SERIES)

      This SUB-ADVISORY AGREEMENT (the "Agreement") is entered into effective as
of the 10th day of December 2002, by and between JANUS CAPITAL MANAGEMENT LLC, a
Delaware limited liability company ("Janus") and PERKINS, WOLF, MCDONNELL AND
COMPANY, a Delaware corporation ("PWM").

      WHEREAS, Janus has entered into an Investment Advisory Agreement (the
"Advisory Agreement") with Janus Adviser Series, a Delaware business trust (the
"Trust") and an open-end, management investment company registered under the
Investment Company Act of 1940, as amended (the "1940 Act"), with respect to the
Janus Adviser Mid Cap Value Fund, a series of the Trust (the "Fund") pursuant to
which Janus has agreed to provide investment advisory services with respect to
the Fund; and

      WHEREAS, PWM is engaged in the business of rendering investment advisory
services and is registered as an investment adviser under the Investment
Advisers Act of 1940, as amended (the "Advisers Act"); and

      WHEREAS, Janus desires to retain PWM to furnish investment advisory
services with respect to the Fund, and PWM is willing to furnish such services;

      NOW THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties agree as follows:

      1. Duties of PWM. Janus hereby engages the services of PWM as subadviser
in furtherance of the Advisory Agreement. PWM agrees to perform the following
duties, subject to the oversight of Janus and to the overall control of the
officers and the Board of Trustees (the "Trustees") of the Trust:

            (a) PWM shall manage the investment operations of the Fund and the
composition of its investment portfolio, shall determine without prior
consultation with the Trust or Janus, what securities and other assets of the
Fund will be acquired, held, disposed of or loaned, and shall direct Janus with
respect to the execution of trades in connection with such determinations, in
conformity with the investment objectives, policies and restrictions and the
other statements concerning the Fund in the Trust's trust instrument, as amended
from time to time (the "Trust Instrument"), bylaws and registration statements
under the 1940 Act and the Securities Act of 1933, as amended (the "1933 Act"),
the Advisers Act, the rules thereunder and all other applicable federal and
state laws and regulations, and the provisions of the Internal Revenue Code of
1986, as amended (the "Code"), applicable to the Fund as a regulated investment
company;

            (b) PWM shall cause its officers to attend meetings and furnish oral
or written reports, as the Trust or Janus may reasonably require, in order to
keep Janus, the Trustees and
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appropriate officers of the Trust fully informed as to the condition of the
investment portfolio of the Fund, the investment decisions of PWM, and the
investment considerations which have given rise to those decisions;

            (c) PWM shall maintain all books and records required to be
maintained by PWM pursuant to the 1940 Act, the Advisers Act, and the rules and
regulations promulgated thereunder, as the same may be amended from time to
time, with respect to transactions on behalf of the Fund, and shall furnish the
Trustees and Janus with such periodic and special reports as the Trustees or
Janus reasonably may request. PWM hereby agrees that all records which it
maintains for the Fund or the Trust are the property of the Trust, agrees to
permit the reasonable inspection thereof by the Trust or its designees and
agrees to preserve for the periods prescribed under the 1940 Act and the
Advisers Act any records which it maintains for the Trust and which are required
to be maintained under the 1940 Act and the Advisers Act, and further agrees to
surrender promptly to the Trust or its designees any records which it maintains
for the Trust upon request by the Trust;

            (d) PWM shall submit such reports relating to the valuation of the
Fund's assets and to otherwise assist in the calculation of the net asset value
of shares of the Fund as may reasonably be requested;

            (e) PWM shall provide Janus with such assistance and advice as Janus
may reasonably request as to the manner in which to exercise, on behalf of the
Fund, such voting rights, subscription rights, rights to consent to corporate
action and any other rights pertaining to the Fund's assets that may be
exercised, in accordance with any policy pertaining to the same that may be
adopted or agreed to by the Trustees of the Trust, so that Janus may exercise
such rights, or, in the event that the Trust retains the right to exercise such
voting and other rights, to furnish the Trust with advice as may reasonably be
requested as to the manner in which such rights should be exercised;

            (f) At such times as shall be reasonably requested by the Trustees
or Janus, PWM shall provide the Trustees and Janus with economic, operational
and investment data and reports, including without limitation all information
and materials reasonably requested by or requested to be delivered to the
Trustees of the Trust pursuant to Section 15(c) of the 1940 Act, and shall make
available to the Trustees and Janus any economic, statistical and investment
services normally available to similar investment company clients of PWM; and

            (g) PWM will provide to Janus for regulatory filings and other
appropriate uses materially accurate and complete information relating to PWM as
may be reasonably requested by Janus from time to time and, notwithstanding
anything herein to the contrary, PWM shall be liable to Janus for all damages,
costs and expenses, including without limitation reasonable attorney's fees
(hereinafter referred to collectively as "Damages"), incurred by Janus as a
result of any material inaccuracies or omissions in such information provided by
PWM to Janus, provided, however, that PWM shall not be liable to the extent that
any Damages are based upon inaccuracies or omissions made in reliance upon
information furnished to PWM by Janus.

      2. Further Obligations. In all matters relating to the performance of this
Agreement, PWM shall act in conformity with the Trust's Trust Instrument, bylaws
and currently effective


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registration statements under the 1940 Act and the 1933 Act and any amendments
or supplements thereto (the "Registration Statements") and with the written
policies, procedures and guidelines of the Fund, and written instructions and
directions of the Trustees and Janus and shall comply with the requirements of
the 1940 Act, the Advisers Act, the rules thereunder, and all other applicable
federal and state laws and regulations. Janus agrees to provide to PWM copies of
the Trust's Trust Instrument, bylaws, Registration Statement, written policies,
procedures and guidelines and written instructions and directions of the
Trustees and Janus, and any amendments or supplements to any of them at, or, if
practicable, before the time such materials become effective.

      3. Obligations of Janus. Janus shall have the following obligations under
this Agreement:

            (a) To keep PWM continuously and fully informed (or cause the
custodian of the Fund's assets to keep PWM so informed) as to the composition of
the investment portfolio of the Fund and the nature of all of the Fund's assets
and liabilities from time to time;

            (b) To furnish PWM with a certified copy of any financial statement
or report prepared for the Fund by certified or independent public accountants
and with copies of any financial statements or reports made to the Fund's
shareholders or to any governmental body or securities exchange; and

            (c) To furnish PWM with any further materials or information which
PWM may reasonably request to enable it to perform its function under this
Agreement.

      4. Compensation. For PWM's services under this Agreement, the Fund shall
pay to PWM a fee equal to 50% of the advisory fee payable to Janus from the Fund
(calculated after any fee waivers). Such fee shall be computed and accrued daily
and payable monthly as of the last day of each month during which or part of
which this Agreement is in effect and shall be paid at the same time and in the
same amount as the fees payable to Janus. For the month during which this
Agreement becomes effective and the month during which it terminates, however,
there shall be an appropriate proration of the fee payable for such month based
on the number of calendar days of such month during which the Agreement is
effective.

      5. Expenses. PWM shall pay all its own costs and expenses incurred in
rendering its service under this Agreement.

      6. Representations of PWM. PWM hereby represents, warrants and covenants
to Janus as follows:

            (a) PWM: (i) is registered as an investment adviser under the
Advisers Act and will continue to be so registered for so long as this Agreement
remains in effect; (ii) is not prohibited by the 1940 Act or the Advisers Act
from performing the services contemplated by this Agreement; (iii) has met, and
will continue to meet for so long as this Agreement remains in effect, any other
applicable federal or state requirements, or the applicable requirements of any
regulatory or industry self-regulatory organization necessary to be met in order
to perform the services contemplated by this Agreement; (iv) has the legal and
corporate authority to enter into and perform the services contemplated by this
Agreement; and (v) will immediately notify Janus


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of the occurrence of any event that would disqualify PWM from serving as an
investment adviser of an investment company pursuant to Section 9(a) of the 1940
Act or otherwise, and of the institution of any administrative, regulatory or
judicial proceeding against PWM that could have a material adverse effect upon
PWM's ability to fulfill its obligations under this Agreement.

            (b) PWM has adopted a written code of ethics complying with the
requirements of Rule 17j-1 under the 1940 Act and will provide Janus with a copy
of such code of ethics, together with evidence of its adoption. Within 45 days
after the end of the last calendar quarter of each year that this Agreement is
in effect, the president or a vice president of PWM shall certify to Janus that
PWM has complied with the requirements of Rule 17j-1 during the previous year
and that there has been no violation of PWM's code of ethics or, if such a
violation has occurred, that appropriate action was taken in response to such
violation. Upon the written request of Janus, PWM shall permit Janus, its
employees or its agents to examine the reports required to be made to PWM by
Rule 17j-1(c)(1) and all other records relevant to PWM's code of ethics.

            (c) PWM has provided Janus with a copy of its Form ADV as most
recently filed with the U.S. Securities and Exchange Commission ("SEC") and
will, promptly after filing any amendment to its Form ADV with the SEC, furnish
a copy of such amendment to Janus.

            (d) PWM will notify Janus of any change in the identity or control
of its shareholders owning a 10% or greater interest in PWM, or any change that
would constitute a change in control of PWM under the 1940 Act, prior to any
such change if PWM is aware, or should be aware, of any such change, but in any
event as soon as any such change becomes known to PWM.

      7. Term. This Agreement shall become effective as of the date first set
forth above and shall continue in effect until July 1, 2004 unless sooner
terminated in accordance with its terms, and shall continue in effect from year
to year thereafter only so long as such continuance is specifically approved at
least annually by the vote of a majority of the Trustees of the Trust who are
not parties hereto or interested persons of the Trust, Janus or PWM, cast in
person at a meeting called for the purpose of voting on the approval of the
terms of such renewal, and by either the Trustees of the Trust or the
affirmative vote of a majority of the outstanding voting securities of the Fund.
The annual approvals provided for herein shall be effective to continue this
Agreement from year to year if given within a period beginning not more than
ninety (90) days prior to July 1 of each applicable year, notwithstanding the
fact that more than three hundred sixty-five (365) days may have elapsed since
the date on which such approval was last given.

      8. Termination. This Agreement may be terminated at any time, without
penalty, by the Trustees or by the shareholders of the Fund acting by vote of at
least a majority of its outstanding voting securities, provided in any such case
that 60 days' advance written notice of termination be given to PWM at its
principal place of business. This Agreement may also be terminated by Janus or
the Trust: (i) by giving 60 days' advance written notice of termination to PWM;
(ii) upon a material breach by PWM of any of the representations and warranties
set forth in Section 6 of this Agreement, if such breach shall not have been
cured within a 20-day period after notice of such breach; or (iii) if PWM
becomes unable to discharge its duties and


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obligations under this Agreement. This Agreement may be terminated by PWM at any
time, without penalty: (i) by giving 60 days' advance written notice of
termination to Janus and to the Trust; or (ii) upon a material breach by Janus
of any of the obligations set forth in Section 3 of this Agreement, if such
breach shall not have been cured within a 20-day period after notice of such
breach. In addition, this Agreement shall terminate, without penalty, upon the
termination of the Advisory Agreement.

      9. Assignment. This Agreement shall automatically terminate in the event
of its assignment.

      10. Amendments. This Agreement may be amended by the parties only in a
written instrument signed by the parties to this Agreement and only if such
amendment is specifically approved (i) by a majority of the Trustees, including
a majority of the Trustees who are not interested persons (as that phrase is
defined in Section 2(a)(19) of the 1940 Act) of the Trust or Janus, PWM or their
affiliates, and (ii) if required by applicable law, by the affirmative vote of a
majority of the outstanding voting securities of the Fund (as that phrase is
defined in Section 2(a)(42) of the 1940 Act).

      11. Limitation on Personal Liability. All parties to this Agreement
acknowledge and agree that the Trust is a series trust and all debts,
liabilities, obligations and expenses incurred, contracted for or otherwise
existing with respect to a particular series shall be enforceable against the
assets held with respect to such series only, and not against the assets of the
Trust generally or against the assets held with respect to any other series and
further that no Trustee, officer or holder of shares of beneficial interest of
the Trust shall be personally liable for any of the foregoing.

      12. Limitation of Liability of PWM. Janus will not seek to hold PWM, and
PWM shall not be, liable for any error of judgment or mistake of law or for any
loss arising out of any investment or for any act or omission taken with respect
to the Fund, except for willful misfeasance, bad faith or gross negligence in
the performance of its duties, or by reason of reckless disregard of its
obligations and duties hereunder and except to the extent otherwise provided by
law. As used in this section, "PWM" shall include any affiliate of PWM
performing services for the Fund contemplated hereunder and directors, officers
and employees of PWM and such affiliates.

      13. Activities of PWM. The services of PWM hereunder are not to be deemed
to be exclusive, and PWM is free to render services to other parties, so long as
its services under this Agreement are not materially adversely affected or
otherwise impaired thereby. Nothing in this Agreement shall limit or restrict
the right of any director, officer or employee of PWM to engage in any other
business or to devote his or her time and attention in part to the management or
other aspects of any other business, whether of a similar or a dissimilar
nature. It is understood that Trustees, officers and shareholders of the Trust
are or may become interested in PWM as directors, officers and shareholders of
PWM, that directors, officers, employees and shareholders of PWM are or may
become similarly interested in the Trust, and that PWM may become interested in
the Trust as a shareholder or otherwise.


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      14. Third Party Beneficiary. The parties expressly acknowledge and agree
that the Trust is a third party beneficiary of this Agreement and that the Trust
shall have the full right to sue upon and enforce this Agreement in accordance
with its terms as if it were a signatory hereto. Any oversight, monitoring or
evaluation of the activities of PWM by Janus, the Trust or the Fund shall not
diminish or relieve in any way the liability of PWM for any of its duties and
responsibilities under this Agreement.

      15. Notices. Any notice or other communication required to be given
pursuant to this Agreement shall be deemed duly given if delivered personally or
by overnight delivery service or mailed by certified or registered mail, return
receipt requested and postage prepaid, or sent by facsimile addressed to the
parties at their respective addresses set forth below, or at such other address
as shall be designated by any party in a written notice to the other party.

            (a) To Janus at:

                Janus Capital Management LLC
                100 Fillmore Street
                Denver, Colorado  80206
                Attention:  General Counsel
                Phone:  (303) 333-3863
                Fax:  (303) 316-5728

            (b) To PWM at:

                Perkins, Wolf, McDonnell and Company
                53 W. Jackson Boulevard
                Suite 818
                Chicago, Illinois  60604
                Attention:  President
                Phone:  (312) 922-0355
                Fax:  (312) 922-0418

            (c) To the Trust at:

                Janus Adviser Series
                100 Fillmore Street
                Denver, Colorado  80206
                Attention:  General Counsel
                Phone:  (303) 333-3863
                Fax:  (303) 316-5728

      16. Certain Definitions. The terms "vote of a majority of the outstanding
voting securities," "assignment," "approved at least annually," and "interested
persons" shall have the respective meanings specified in the 1940 Act, as now in
effect or hereafter amended, and the rules and regulations thereunder, subject
to such orders, exemptions and interpretations as may be issued by the SEC under
the 1940 Act and as may be then in effect.


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      17. Governing Law. This Agreement shall be construed in accordance with
the laws of the State of Colorado (without giving effect to the conflicts of
laws principles thereof) and the 1940 Act. To the extent that the applicable
laws of the State of Colorado conflict with the applicable provisions of the
1940 Act, the latter shall control.

      IN WITNESS WHEREOF, the parties have caused this Agreement to be executed
by their duly authorized officers designated below as of the day and year first
above written.

                                    JANUS CAPITAL MANAGEMENT LLC


                                    By:_________________________________________


                                    PERKINS, WOLF, MCDONNELL AND COMPANY


                                    By:_________________________________________


                                    ACKNOWLEDGMENT:

                                    The undersigned acknowledges that it is
                                    obligated to compensate PWM for its services
                                    in accordance with the provisions of Section
                                    4 of this Agreement.

                                    JANUS ADVISER SERIES on behalf of Janus
                                    Adviser Mid Cap Value Fund


                                    By:_________________________________________


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