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                                                                     EXHIBIT 4.3

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                         SECOND SUPPLEMENTAL INDENTURE




                                   __________




                        A I M MANAGEMENT GROUP INC., as
                    successor Company by transfer of assets,

                             A I M ADVISORS, INC.,
                                 as Guarantor,

                                      and

                              FLEET NATIONAL BANK,
                                   as Trustee



                   Dated as of 10:30 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, as
supplemented by a First Supplemental Indenture dated as of 9:30 a.m., February
28, 1997, relating to 9% Senior Notes due November 15, 2003 between AVZ Inc.,
successor Company by merger, A I M Advisors, Inc., as Guarantor, and Fleet
National Bank, as Trustee.

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         SECOND SUPPLEMENTAL INDENTURE dated as of 10:30 a.m. Eastern Standard
Time, February 28, 1997, between A I M MANAGEMENT GROUP INC. (formerly known as
A I M Management Group Acquisition Corp.), 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 ("Old
AIM"), heretofore executed and delivered to the Trustee an Indenture dated as
of November 3, 1993, as supplemented by a First Supplemental Indenture dated as
of 9:30 a.m., February 28, 1997 (the "Indenture"), providing for the creation
of Old 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 (the "Merger") of Old AIM into
AVZ Inc., a Delaware corporation ("AVZ"), pursuant to an Agreement and Plan of
Merger, dated as of November 4, 1996, as subsequently amended, by and among Old
AIM, INVESCO PLC, a company organized under the laws of England, and INVESCO
Group Services, Inc., a Delaware corporation, Old AIM has been merged into AVZ
and in connection therewith AVZ assumed, by operation of law, all of Old AIM's
debts, liabilities, duties and obligations, including Old AIM's obligations
under the Securities and the Indenture, and executed the First Supplemental
Indenture; and

         WHEREAS, following the Merger, AVZ contributed all of Old AIM's assets
and debts, liabilities, duties and obligations which had been assumed by AVZ,
including obligations under the Securities and the Indenture, to the Company,
and the Company accepted such assets and assumed all such debts, liabilities,
duties and obligations, including obligations under the Securities and the
Indenture, which transfer and assumption is contemplated by Section 801 of the
Indenture, provided this Second Supplemental Indenture is executed and
delivered; and

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

         WHEREAS, Section 802 of the Indenture provides that upon such
assumption, the predecessor, being AVZ, shall be released from all the
obligations under the Securities and the Indenture; and




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         WHEREAS, the Company, as an indirect wholly owned subsidiary of
INVESCO PLC, a public company, will not have any Independent Directors, all
Independent Directors being directors of INVESCO PLC; and

         WHEREAS, Section 1010 of the Indenture requires that certain
transactions with Affiliates be approved by a majority of the Independent
Directors of the Board of Directors of the Company; and

         WHEREAS, Section 901 of the Indenture provides that supplemental
indentures may be executed without the consent of any Holders, at any time and
from time to time for among other purposes: to evidence the succession of
another Person to the Company; to add to the covenants of the Company for the
benefit of the Holders; to cure any ambiguity or to correct or supplement any
provision of the Indenture which may be defective or inconsistent with any
other provision of the Indenture; or to clarify or make any other provisions
with respect to matters or questions arising under the Indenture provided that
such clarification or provision thus made shall not adversely affect the
interest of the Holders; and

         WHEREAS, the Company desires and has requested the Trustee to join
with it in entering into this Second Supplemental Indenture for the purpose of
amending Section 1010 of the Indenture to provide for approval of Affiliate
transactions by the Independent Directors of the Board of Directors of the
Person controlling the Company that has Independent Directors; and

         WHEREAS, the execution and delivery of this Second 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 Second
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, 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 INVESCO

         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 AVZ in the Indenture as if the Company had been the original
maker of the Securities, and also hereby expressly



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assumes each and every covenant and condition of AVZ in each Security
outstanding on the date of this Second 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 Second Supplemental Indenture, and under the
Securities.


                                   ARTICLE 3

                                 RELEASE OF AVZ

         SECTION 3.01.  Release.  Pursuant to Section 802 of the Indenture, AVZ
is hereby released from the obligations under the Securities and the Indenture.

                                   ARTICLE 4

                           AMENDMENT TO SECTION 1010

         SECTION 4.01.  Section 1010 of the Indenture is amended to read in its
entirety as follows:

                          The Company will not, and will not permit any
                 Subsidiary to, directly or indirectly, enter into or suffer to
                 exist any transaction or series of related transactions
                 (including, without limitation, the sale, purchase, exchange
                 or lease of assets, property or services) with any Affiliate
                 of the Company (other than the Company or a Wholly Owned
                 Subsidiary) unless (i) such transaction or series of related
                 transactions is on terms that are no less favorable to the
                 Company or such Subsidiary, as the case may be, than would be
                 available in a comparable transaction in arm's-length
                 dealings with an unrelated third party and (ii) with respect
                 to any one transaction or series of related transactions
                 involving aggregate payments in excess of $1 million, the
                 Company delivers an officers' certificate to the Trustee
                 certifying that such transaction or series of related
                 transactions complies with clause (i) above and such
                 transaction or series of related transactions has received the
                 approval of a majority





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                 of the Independent Directors of the Board of Directors of the
                 Company, or in the event the Company does not have Independent
                 Directors, of the Person controlling the Company that has
                 directors who are independent within the meaning of the term
                 "Independent Directors" if applied to such Person; provided
                 that such provision shall not apply to (A) any transaction
                 arising out of any agreement existing on the date of this
                 Indenture and set forth on Schedule II to this Indenture; (B)
                 transactions between the Company or any Subsidiary and any
                 Fund; (C) loans and advances (or guarantees in respect thereof
                 and payments thereunder) made to officers or employees of the
                 Company or any Subsidiary related to the Company's or such
                 Subsidiary's business, in an amount not to exceed $500,000 in
                 any year; and (D) any transaction permitted under paragraph
                 (b) of Section 1009.

                                   ARTICLE 5

                               TRUSTEE DISCLAIMER

         SECTION 5.01.  Trustee Disclaimer.  The Trustee has accepted the
amendment of the Indenture effected by this Second 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 Second 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 6

                            MISCELLANEOUS PROVISIONS

         SECTION 6.01.  Terms Defined.  For all purposes of this Second
Supplemental Indenture, except as otherwise defined or unless the context
otherwise requires, terms used in capitalized form in this Second Supplemental
Indenture and defined in the Indenture have the meanings specified in the
Indenture.





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         SECTION 6.02.  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 Second Supplemental Indenture is
an indenture supplemental to and in implementation of the Indenture, and said
Indenture and this Second Supplemental Indenture shall henceforth be read
together.

         SECTION 6.03.  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 Second Supplemental Indenture, shall be:

                          A I M Management Group Inc.
                          11 Greenway Plaza, Suite 1919
                          Houston, TX  77046-1173
                          Attention:  President

         with a copy to:

                          A I M Management Group Inc.
                          11 Greenway Plaza, Suite 1919
                          Houston, TX  77046-1173
                          Attention:  General Counsel

         SECTION 6.04.  Governing Law.  This Second 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 6.05.  Successors.  All agreements of the Company, the
Guarantor and the Trustee in this Second Supplemental Indenture shall bind
their respective successors.

         SECTION 6.06.  Effective Date.  This Second 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 6.07.  Counterparts.  This Second 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 Second
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]                        A I M MANAGEMENT GROUP INC.


ATTEST:
                                        By /s/ ROBERT H. GRAHAM
/s/ CAROL F. RELIHAN                       ----------------------------------
----------------------------------         President
Title: Secretary


[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 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 Management
Group 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 Public            

Notary Seal



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 Public            


Notary Seal





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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 Public            


Notary Seal





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