Document:

<PAGE>

                                                                Exhibit 4(aaaaa)

                                  AMENDMENT TO

                              JANUS ADVISER SERIES

                          INVESTMENT ADVISORY AGREEMENT

                          JANUS ADVISER WORLDWIDE FUND

         THIS AMENDMENT is made this 14th day of June, 2006, between JANUS
ADVISER SERIES, a Delaware statutory trust (the "Trust"), and JANUS CAPITAL
MANAGEMENT LLC, a Delaware limited liability company ("JCM").

                                   WITNESSETH

         WHEREAS, the Trust and JCM are parties to an Investment Advisory
Agreement on behalf of Janus Adviser Worldwide Fund (the "Fund"), dated July 1,
2004, amended February 1, 2006 (the "Agreement");

         WHEREAS, the parties desire to amend the Agreement as set forth in
greater detail below;

         WHEREAS, pursuant to Section 11 of the Agreement, any amendment to the
Agreement is subject to approval (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 Investment Company Act of 1940, as amended
(the "1940 Act")) of any party to the Agreement, 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);

         WHEREAS, the parties have obtained Trustee approval as set forth above,
and the parties agree that a shareholder vote is not required to amend the
Agreement; and

         NOW, THEREFORE, in consideration of the premises and of the mutual
agreements set forth below, the parties agree to amend the Agreement as follows:

         1. Sections 5, 6 and 7 of the Agreement shall be deleted in their
entirety and replaced with the following:

                  "5. Compensation. The Trust shall pay to JCM for its services
         pursuant to this Agreement a monthly base fee of 1/12 of 0.60% of the
         average daily closing net asset value of the Fund, adjusted by a
         performance fee as set forth in Schedule A. For any period less than a
         month during which this Agreement is in effect, the base fee shall be
         prorated according to the proportion which such period bears to a full
         month of 28, 29, 30 or 31 days, as the case may be.

<PAGE>

                     6. Expenses Borne by JCM. In addition to the expenses which
         JCM may incur in the performance of its investment advisory functions
         and other services 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," as defined in the
                                    1940 Act, of JCM, and except as otherwise
                                    provided in Section 7; and

                           (b)      Rental of offices of the Trust.

                  7. 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 3 and 6 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," as defined in
         the 1940 Act, of JCM; compensation and related expenses of the Chief
         Compliance Officer of the Trust and compliance staff, as authorized
         from time to time by the Trustees of the Trust; 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 to Fund shareholders; 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."

         2. The parties acknowledge that the Agreement, as amended, remains in
full force and effect as of the date of this Amendment, and that this Amendment,
together with the Agreement and any prior amendments, contains the entire
understanding and the full and complete agreement of the parties and supercedes
and replaces any prior understandings and agreements among the parties
respecting the subject matter hereof.

<PAGE>

         3. This Amendment may be contemporaneously executed in two or more
counterparts, each of which shall be deemed an original but all of which
together shall constitute one and the same instrument.

         IN WITNESS WHEREOF, the parties have caused their duly authorized
officers to execute this Amendment as of the date first above written.

                                         JANUS CAPITAL MANAGEMENT LLC

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

                                         JANUS ADVISER SERIES

                                         By: /s/ Stephanie Grauerholz-Lofton
                                             -----------------------------------
                                             Stephanie Grauerholz-Lofton
                                             Vice President and Secretary<PAGE>

                                                                Exhibit 4(bbbbb)

                                  AMENDMENT TO

                              JANUS ADVISER SERIES

                             SUB-ADVISORY AGREEMENT

                        JANUS ADVISER MID CAP VALUE FUND

         THIS AMENDMENT is made this 14th day of June, 2006, between JANUS
CAPITAL MANAGEMENT LLC, a Delaware limited liability company ("Janus"), and
Perkins, Wolf, McDonnell and Company, LLC a Delaware limited liability company
("PWM").

                                   WITNESSETH

         WHEREAS, Janus and PWM are parties to a Sub-Advisory Agreement on
behalf of Janus Adviser Mid Cap Value Fund (the "Fund"), a series of Janus
Adviser Series, a Delaware statutory trust (the "Trust"), dated July 1, 2004
(the "Agreement");

         WHEREAS, the parties desire to amend the Agreement as set forth in
greater detail below;

         WHEREAS, pursuant to Section 10 of the Agreement, any amendment to the
Agreement is subject to approval by (i) 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);

         WHEREAS, the parties have obtained Trustee approval as set forth above,
and the parties agree that a shareholder vote is not required to amend the
Agreement; and

         WHEREAS, the effective date of the termination of the Agreement has
been changed to February 1, 2007;

         NOW, THEREFORE, in consideration of the premises and of the mutual
agreements set forth below, the parties agree to amend the Agreement as follows:

         1. Section 7 of the Agreement shall be deleted in its entirety and
replaced with the following:

                  "10. Term. This Agreement shall become effective as of the
                  date first set forth above and 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

<PAGE>

                  specifically approved at least annually by (a) 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 (b) 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."

         2. The parties acknowledge that the Agreement, as amended, remains in
full force and effect as of the date of this Amendment, and that this Amendment,
together with the Agreement and any prior amendments, contains the entire
understanding and the full and complete agreement of the parties and supercedes
and replaces any prior understandings and agreements among the parties
respecting the subject matter hereof.

         3. This Amendment may be contemporaneously executed in two or more
counterparts, each of which shall be deemed an original but all of which
together shall constitute one and the same instrument.

         IN WITNESS WHEREOF, the parties have caused their duly authorized
officers to execute this Amendment as of the date first above written.

                                     JANUS CAPITAL MANAGEMENT LLC

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

                                     Perkins, Wolf, McDonnell and Company, LLC

                                     By: /s/ Gregory E. Wolf
                                         ---------------------------------------
                                     Name: Gregory E. Wolf
                                           -------------------------------------
                                     Title: Chief Operations Officer
                                            ------------------------------------

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00110-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00110-of-00352.parquet"}]]