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                                                                      EXHIBIT 11




              [BALLARD SPAHR ANDREWS & INGERSOLL, LLP LETTERHEAD]





                                  May 11, 2001


AIM Funds Group
11 Greenway Plaza
Suite 100
Houston, TX 77046

                  RE:  Shares of AIM Balanced Fund

Ladies and Gentlemen:

                  We have acted as counsel to AIM Funds Group, a Delaware
business trust (the "Company"), in connection with that certain Agreement and
Plan of Reorganization (the "Plan") among the Company, on behalf of its series
portfolio, AIM Balanced Fund ("Balanced Fund"), AIM Advisor Funds, a Delaware
business trust ("AAF"), on behalf of its series portfolio, AIM Advisor Flex
Fund ("Flex Fund") and A I M Advisors, Inc., a Delaware corporation.

                  The Plan provides for the reorganization of Flex Fund with and
into Balanced Fund (the "Reorganization"). Pursuant to the Plan, all of the
assets of Flex Fund will be transferred to Balanced Fund. Balanced Fund will
assume all of the liabilities of Flex Fund and the Company will issue Class A
shares of Balanced Fund to Flex Fund's Class A shareholders, Class B shares of
Balanced Fund to Flex Fund's Class B shareholders and Class C shares of Balanced
Fund to Flex Fund's Class C shareholders. The value of each Flex Fund
shareholder's account with Balanced Fund after the Reorganization will be the
same as the value of such shareholder's account with Flex Fund prior to the
Reorganization.

                  The opinion expressed below is based on the assumption that a
Registration Statement on Form N-14 with respect to the Class A, Class B and
Class C shares of Balanced Fund to be issued to the Flex Fund shareholders
pursuant to the Plan (the "Balanced Fund Shares") will have been filed by the
Company with the Securities and Exchange Commission and will have become
effective before the Reorganization occurs.

                  Based on the foregoing, we are of the opinion that the
Balanced Fund Shares, when issued by the Company to the shareholders of Flex
Fund in accordance with the terms and conditions of the Plan, will be legally
issued, fully paid and nonassessable.

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                  We express no opinion concerning the laws of any jurisdiction
other than the federal laws of the United States of America and the laws of the
State of Delaware.

                  We consent to the filing of this opinion as an Exhibit to the
Company's Registration Statement on Form N-14 and to the references to this firm
in such Registration Statement.



                                Very truly yours,

                                /s/ Ballard Spahr Andrews & Ingersoll, LLP








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