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                                                                  Exhibit 4(yyy)

                               JANUS ASPEN SERIES

                          INVESTMENT ADVISORY AGREEMENT

                             MONEY MARKET PORTFOLIO

      THIS INVESTMENT ADVISORY AGREEMENT (the "Agreement") is made this 3rd day
of April, 2002, as amended February 1, 2006, between JANUS ASPEN SERIES, a
Delaware business trust (the "Trust"), and JANUS CAPITAL MANAGEMENT LLC, a
Delaware limited liability company ("JCM").

                              W I T N E S S E T H:

      WHEREAS, the Trust is registered as an open-end management investment
company under the Investment Company Act of 1940, as amended (the "1940 Act"),
and has registered its shares for public offering under the Securities Act of
1933, as amended (the "1933 Act"); and

      WHEREAS, the Trust is authorized to create separate funds, each with its
own separate investment portfolio of which the beneficial interests are
represented by a separate series of shares; one of such funds created by the
Trust being designated as the Money Market Portfolio (the "Fund"); and

      WHEREAS, the Trust and JCM deem it mutually advantageous that JCM should
be appointed as the investment adviser to the Fund.

      NOW, THEREFORE, the parties agree as follows:

      1. Investment Advisory Services. JCM shall determine the securities or
other assets to be purchased, sold or held and shall place orders for the
purchase or sale of such securities or other assets. JCM shall furnish
continuous advice and recommendations to the Fund, and have authority to act
with respect thereto, as to the acquisition, holding, or disposition of any or
all of the securities or other assets which the Fund may own or contemplate
acquiring from time to time. JCM shall give due consideration to the investment
policies and restrictions and the other statements concerning the Fund in the
Trust Instrument, bylaws, and registration statements under the 1940 Act and the
1933 Act, and to the provisions of the Internal Revenue Code, as amended from
time to time, applicable to the Fund as a regulated investment company and as a
funding vehicle for variable insurance contracts. In addition, JCM shall cause
its officers to attend meetings and furnish oral or written reports, as the
Trust may reasonably require, in order to keep the Trustees and appropriate
officers of the Trust fully informed as to the condition of the investment
portfolio of the Fund.

      2. Other Services. JCM is hereby authorized (to the extent the Trust has
not otherwise contracted) but not obligated (to the extent it so notifies the
Trustees at least 60 days in

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advance), to perform (or arrange for the performance by affiliates of) the
management and administrative services necessary for the operation of the Fund.
JCM is specifically authorized, on behalf of the Trust, to conduct relations
with custodians, depositories, transfer and pricing agents, accountants,
attorneys, underwriters, brokers and dealers, corporate fiduciaries, insurance
company separate accounts, insurers, banks and such other persons in any such
other capacity deemed by JCM to be necessary or desirable. JCM shall generally
monitor and report to Fund officers the Fund's compliance with investment
policies and restrictions as set forth in the currently effective prospectus and
statement of additional information relating to the shares of the Fund under the
Securities Act of 1933, as amended. JCM shall make reports to the Trustees of
its performance of services hereunder upon request therefor and furnish advice
and recommendations with respect to such other aspects of the business and
affairs of the Fund as it shall determine to be desirable. JCM is also
authorized, subject to review by the Trustees, to furnish such other services as
JCM shall from time to time determine to be necessary or useful to perform the
services contemplated by this Agreement.

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

            (a)   to keep JCM continuously and fully informed as to the
                  composition of its investment portfolio and the nature of all
                  of its assets and liabilities from time to time;

            (b)   to furnish JCM with a certified copy of any financial
                  statement or report prepared for it by certified or
                  independent public accountants and with copies of any
                  financial statements or reports made to its shareholders or to
                  any governmental body or securities exchange;

            (c)   to furnish JCM with any further materials or information which
                  JCM may reasonably request to enable it to perform its
                  function under this Agreement; and

            (d)   to compensate JCM for its services and reimburse JCM for its
                  expenses incurred hereunder in accordance with the provisions
                  hereof.

      4. Compensation. The Trust shall pay to JCM for its investment advisory
services a fee, calculated and payable for each day that this Agreement is in
effect, of 1/365 of 0.25% of the aggregate closing net asset value of the shares
of the Fund for each day of such month.

      5. Expenses Borne by JCM. In addition to the expenses which JCM may incur
in the performance of its investment advisory functions under this Agreement,
and the expenses which it may expressly undertake to incur and pay under other
agreements with the Trust or otherwise, JCM shall incur and pay the following
expenses relating to the Fund's operations without reimbursement from the Fund:

            (a)   Reasonable compensation, fees and related expenses of the
                  Trust's officers and its Trustees, except for such Trustees
                  who are not interested persons of JCM; and

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            (b)   Rental of offices of the Trust.

      6. Expenses Borne by the Trust. The Trust assumes and shall pay all
expenses incidental to its organization, operations and business not
specifically assumed or agreed to be paid by JCM pursuant to Sections 2 and 5
hereof, including, but not limited to, investment adviser fees; any
compensation, fees, or reimbursements which the Trust pays to its Trustees who
are not interested persons of JCM; compensation of the Fund's custodian,
transfer agent, registrar and dividend disbursing agent; legal, accounting,
audit and printing expenses; administrative, clerical, recordkeeping and
bookkeeping expenses; brokerage commissions and all other expenses in connection
with execution of portfolio transactions (including any appropriate commissions
paid to JCM or its affiliates for effecting exchange listed, over-the-counter or
other securities transactions); interest; all federal, state and local taxes
(including stamp, excise, income and franchise taxes); costs of stock
certificates and expenses of delivering such certificates to purchasers thereof;
expenses of local representation in Delaware; expenses of shareholders' meetings
and of preparing, printing and distributing proxy statements, notices, and
reports to shareholders; expenses of preparing and filing reports and tax
returns with federal and state regulatory authorities; all expenses incurred in
complying with all federal and state laws and the laws of any foreign country
applicable to the issue, offer, or sale of shares of the Fund, including, but
not limited to, all costs involved in the registration or qualification of
shares of the Fund for sale in any jurisdiction, the costs of portfolio pricing
services and compliance systems, and all costs involved in preparing, printing
and mailing prospectuses and statements of additional information of the Fund;
and all fees, dues and other expenses incurred by the Trust in connection with
the membership of the Trust in any trade association or other investment company
organization. To the extent that JCM shall perform any of the above described
administrative and clerical functions, including transfer agency, registry,
dividend disbursing, recordkeeping, bookkeeping, accounting and blue sky
monitoring and registration functions, and the preparation of reports and
returns, the Trust shall pay to JCM compensation for, or reimburse JCM for its
expenses incurred in connection with, such services as JCM and the Trust shall
agree from time to time, any other provision of this Agreement notwithstanding.

      7. Termination. This Agreement may be terminated at any time, without
penalty, by the Trustees of the Trust, or by the shareholders of the Fund acting
by vote of at least a majority of its outstanding voting securities, provided in
either case that sixty (60) days advance written notice of termination be given
to JCM at its principal place of business. This Agreement may be terminated by
JCM at any time, without penalty, by giving sixty (60) days advance written
notice of termination to the Trust, addressed to its principal place of
business. The Trust agrees that, consistent with the terms of the Trust
Instrument, the Trust shall cease to use the name "Janus" in connection with the
Fund as soon as reasonably practicable following any termination of this
Agreement if JCM does not continue to provide investment advice to the Fund
after such termination.

      8. Assignment. This Agreement shall terminate automatically in the event
of any assignment of this Agreement.

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      9. Term. This Agreement shall continue in effect until February 1, 2007,
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 any
such party, 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 February 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.

      10. Amendments. This Agreement may be amended by the parties 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 JCM and, if required by
applicable law, (ii) 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. Other Series. The Trustees shall determine the basis for making an
appropriate allocation of the Trust's expenses (other than those directly
attributable to the Fund) between the Fund and the other series of the Trust.

      12. Limitation of Personal Liability. All the parties hereto acknowledge
and agree that all liabilities of the Trust arising, directly or indirectly,
under this Agreement, of any and every nature whatsoever, shall be satisfied
solely out of the assets of the Fund and that no Trustee, officer or holder of
shares of beneficial interest of the Trust shall be personally liable for any of
the foregoing liabilities. The Trust Instrument describes in detail the
respective responsibilities and limitations on liability of the Trustees,
officers and holders of shares of beneficial interest of the Trust.

      13. Limitation of Liability of JCM. JCM 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 Trust, 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 13,
"JCM" shall include any affiliate of JCM performing services for the Trust
contemplated hereunder and directors, officers and employees of JCM and such
affiliates.

      14. Activities of JCM. The services of JCM to the Trust hereunder are not
to be deemed to be exclusive, and JCM and its affiliates are free to render
services to other parties. It is understood that trustees, officers and
shareholders of the Trust are or may become interested in JCM as directors,
officers and shareholders of JCM, that directors, officers, employees and
shareholders of JCM are or may become similarly interested in the Trust, and
that JCM may become interested in the Trust as a shareholder or otherwise.

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      15. Certain Definitions. The terms "vote of a majority of the outstanding
voting securities," "assignment" and "interested persons" when used herein,
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 Securities and
Exchange Commission under said Act and as may be then in effect.

      IN WITNESS WHEREOF, the parties have caused their duly authorized officers
to execute this Investment Advisory Agreement as of the amended date and year
first above written.

                        JANUS CAPITAL MANAGEMENT LLC

                        By: /s/ David R. Martin
                            ----------------------------------------------------
                            David R. Martin, Chief Financial Officer and
                            Executive Vice President

                        JANUS ASPEN SERIES

                        By: /s/ Kelley A. Howes
                            ----------------------------------------------------
                            Kelley A. Howes, President and Chief
                            Executive Officer

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