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                                                                     EXHIBIT 4.2

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                          FIRST SUPPLEMENTAL INDENTURE




                                   __________




                                  AVZ INC., as
                          successor Company by merger,

                             A I M ADVISORS, INC.,
                                 as Guarantor,

                                      and

                              FLEET NATIONAL BANK,
                                   as Trustee



                    Dated as of 9:30 a.m. February 28, 1997



                                   __________





         Supplement to Indenture dated as of November 3, 1993, relating to 9%
Senior Notes due November 15, 2003, between A I M Management Group Inc., as
Issuer, A I M Advisors, Inc., as Guarantor, and Fleet National Bank (formerly
known as Shawmut Bank Connecticut, National Association), as Trustee




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         FIRST SUPPLEMENTAL INDENTURE dated as of 9:30 a.m. February 28, 1997,
between AVZ INC., a Delaware corporation (the "Company"), A I M ADVISORS, INC.,
a Delaware corporation (the "Guarantor"), and FLEET NATIONAL BANK (formerly
known as Shawmut Bank Connecticut, National Association), as Trustee under the
Indenture hereinafter mentioned (in such capacity, the "Trustee").

         WHEREAS, A I M Management Group Inc., a Delaware corporation ("AIM"),
heretofore executed and delivered to the Trustee an Indenture dated as of
November 3, 1993 (the "Indenture"), providing for the creation of AIM's 9%
Senior Notes, due November 15, 2003 (the "Securities"); and

         WHEREAS, there have been issued and are now outstanding under the
Indenture, Securities in the aggregate principal amount of $97,250,000; and

         WHEREAS, in connection with the merger of AIM into the Company (the
"Merger"), pursuant to an Agreement and Plan of Merger, dated as of November 4,
1996, as subsequently amended, by and among AIM, INVESCO PLC, a company
organized under the laws of England, and INVESCO Group Services, Inc., a
Delaware corporation, AIM has been merged into the Company and in connection
therewith the Company has assumed, by operation of law, all of AIM's debts,
liabilities, duties and obligations, including AIM's obligations in respect of
the Securities and under the Indenture, which merger and assumption is
contemplated by Section 801 of the Indenture, provided that this First
Supplemental Indenture is executed and delivered; and

         WHEREAS, the Company desires in and by this First Supplemental
Indenture, pursuant to and as contemplated by Sections 801 and 901 of the
Indenture, to expressly assume the covenants, agreements and undertakings of
AIM in the Indenture and in the Securities; and

         WHEREAS, the execution and delivery of this First Supplemental
Indenture has been authorized by a resolution of the Board of Directors of the
Company and the Guarantor; and

         WHEREAS, all conditions and requirements necessary to make this First
Supplemental Indenture a valid and binding instrument in accordance with its
terms have been performed and fulfilled and the execution and delivery hereof
have been in all respects duly authorized;

         NOW, THEREFORE, in consideration of the above premises, and in order
to comply with the terms of Section 801 of the Indenture, each party agrees,
for the benefit of the other and for the equal and ratable benefit of the
Holders of the Securities as follows:

                                   ARTICLE 1

                        ASSUMPTION OF OBLIGATIONS OF AIM
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         SECTION 1.01.  Assumption.  The Company hereby expressly assumes the
due and punctual payment of the principal and premium and interest on all of
the Securities and the performance and observance of each and every covenant
and condition of AIM in the Indenture as if the Company had been the original
maker of the Securities, and also hereby expressly assumes each and every
covenant and condition of AIM in each Security outstanding on the date of this
First Supplemental Indenture.


                                   ARTICLE 2

                            CONSENT OF AIM ADVISORS

         SECTION 2.01.  Consent.  The Guarantor hereby confirms that its
Subsidiary Guarantee shall apply to the Company's obligations under the
Indenture, as amended by this First Supplemental Indenture, and under the
Securities.


                                   ARTICLE 3

                               TRUSTEE DISCLAIMER

         SECTION 3.01.  Trustee Disclaimer.  The Trustee has accepted the
amendment of the Indenture effected by this First Supplemental Indenture and
agrees to execute the trust created by the Indenture as hereby amended, but
only upon the terms and conditions set forth in the Indenture, including the
terms and provisions defining and limiting the liabilities and responsibilities
of the Trustee, and without limiting the generality of the foregoing, the
Trustee shall not be responsible in any manner whatsoever for or with respect
to any of the recitals or statements contained herein, all of which recitals or
statements are made solely by the Company and the Guarantor, or for or with
respect to (a) the validity or sufficiency of this First Supplemental Indenture
or any of the terms or provisions hereof, (b) the proper authorization hereof
by the Company and the Guarantor by corporate action or otherwise, (c) the due
execution hereof by the Company and the Guarantor, and (d) the consequences
(direct or indirect and whether deliberate or inadvertent) of any amendment
herein provided for, and the Trustee makes no representation with respect to
any such matters.

                                   ARTICLE 4

                            MISCELLANEOUS PROVISIONS

         SECTION 4.01.  Terms Defined.  For all purposes of this First
Supplemental Indenture, except as otherwise defined or unless the context
otherwise requires, terms used in capitalized




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form in this First Supplemental Indenture and defined in the Indenture have the
meanings specified in the Indenture.

         SECTION 4.02.  Indenture.  Except as amended hereby, the Indenture and
the Securities are in all respects ratified and confirmed and all terms thereof
shall remain in full force and effect.  This First Supplemental Indenture is an
indenture supplemental to and in implementation of the Indenture, and said
Indenture and this First Supplemental Indenture shall henceforth be read
together.

         SECTION 4.03.  Notices.  The address to which notice to the Company is
to be given pursuant to Section 106 of the Indenture, from and after the date
of this First Supplemental Indenture, shall be:

                          AVZ INC.
                          11 Greenway Plaza, Suite 1919
                          Houston, TX  77046-1173
                          Attention:  Robert H. Graham

         with a copy to:

                          AVZ INC.
                          11 Greenway Plaza, Suite 1919
                          Houston, TX  77046-1173
                          Attention:  Carol F. Relihan

         SECTION 4.04.  Governing Law. This First Supplemental Indenture shall
be governed by and construed in accordance with the internal laws of the State
of New York, without regard to the conflicts of laws rules thereof.

         SECTION 4.05.  Successors.  All agreements of the Company, the
Guarantor and the Trustee in this First Supplemental Indenture shall bind their
respective successors.

         SECTION 4.06.  Effective Date.  This First Supplemental Indenture
shall become a legally effective and binding instrument upon the execution and
delivery hereof by all parties hereto.







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         SECTION 4.07.  Counterparts.  This First Supplemental Indenture may be
signed in any number of counterparts, each of which shall be an original, with
the same effect as if the signatures thereto and hereto were upon the same
instrument.

         IN WITNESS WHEREOF, the parties hereto have caused this First
Supplemental Indenture to be duly executed and their respective corporate seals
to be hereunto affixed and attested, all as of the day and year first above
written.




[Corporate Seal]                             AVZ INC.
                            
                            
ATTEST:                     
                                             By /s/ ROBERT F. McCULLOUGH
                                                ----------------------------
ILLEGIBLE                            
----------------------------
Title:                      
                            
                            

[Corporate Seal]                             A I M ADVISORS, INC.
                            
                            
ATTEST:                     
                                             By /s/ ROBERT H. GRAHAM
                                                ----------------------------
/s/ CAROL F. RELIHAN                             President
----------------------------                              
Title: Secretary                     
                            
                            

[Corporate Seal]                             FLEET NATIONAL BANK,
                                             as Trustee
                            
ATTEST:                     
                                             By /s/ SUSAN T. KELLER
                                                ----------------------------
ILLEGIBLE                                        Vice President
----------------------------                                   
Title: Assistant Vice 
       President                     





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STATE OF NEW YORK                :
                                 :       ss
COUNTY OF NEW YORK               :

         On this 28th day of February, 1997, before me personally came Robert F.
McCullough, to me known, who, being by me duly sworn, did depose and say that he
resides at 3505 Knollwood Drive, Atlanta, GA, that he is Chief Financial Officer
and Vice President of AVZ Inc., one of the corporations described in and which
executed the above instrument; that he knows the corporate seal of said
corporation; that the seal affixed to said instrument is such corporate seal;
that it was so affixed by authority of the Board of Directors of said
corporation; and that he signed his name thereto by like authority.



                                                     /s/ FELIX SARATOVSKY    
                                                     ------------------------
Notary Seal                                               Notary Public



STATE OF TEXAS                    :
                                  :        ss
COUNTY OF HARRIS                  :

         On this 28th day of February, 1997, before me personally came Robert H.
Graham, to me known, who, being by me duly sworn, did depose and say that he
resides at Houston, Texas, that he is President of A I M Advisors, Inc., one of
the corporations described in and which executed the above instrument; that he
knows the corporate seal of said corporation; that the seal affixed to said
instrument is such corporate seal; that it was so affixed by authority of the
Board of Directors of said corporation; and that he signed his name thereto by
like authority.



                                                     /s/ EVA L. BENCZE          
                                                     ------------------------
Notary Seal                                               Notary Public  





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STATE OF CONNECTICUT                       :
                                           :       ss
COUNTY OF HARTFORD                         :

            On this 28th day of February, 1997, before me personally came 
Susan T. Keller, to me known, who, being by me duly sworn, did depose and say
that she resides at 41 Pleasant St, West Hartford CT, that she is Vice-President
of Fleet National Bank, one of the entities described in and which executed the
above instrument; that she knows the corporate seal of said entity; that the
seal affixed to said instrument is such corporate seal; that it was so affixed
by authority of the Board of Directors of said entity; and that she signed her
name thereto by like authority



                                                       /s/ DAWN P. HEINTZ
                                                     ------------------------
Notary Seal                                                Notary Public 





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