AMENDMENT TO THE AGREEMENT AND DECLARATION OF TRUST
                                       OF
                           PIONEER MID-CAP VALUE FUND


         The undersigned, being at least a majority of the Trustees of Pioneer
Mid-Cap Value Fund, a Delaware business trust, acting pursuant to Article IX,
Section 8 of the Agreement and Declaration of Trust dated January 8, 1998 (the
"Declaration"), do hereby amend the Declaration as follows, such amendment to
become effective upon the filing of an amendment to the Trust's Certificate of
Trust with the Secretary of State of the State of Delaware.

         Section 1 of Article 1 of the Declaration is hereby deleted and
replaced with the following:

         Section 1.  NAME: The name of the Trust created by this Declaration of
Trust is "Pioneer Mid Cap Value Fund."

         IN WITNESS WHEREOF, the undersigned being all the Trustees of the Trust
have executed this instrument as of the date first written above.


         /S/ MARY K. BUSH
         ----------------
         Mary K. Bush As Trustee and not individually



         /S/ JOHN F. COGAN, JR.
         ----------------------
         John F. Cogan, Jr. As Trustee and not individually



         /S/ RICHARD H. EGDAHL
         ---------------------
         Richard H. Egdahl As Trustee and not individually



         /S/ MARGARET B.W. GRAHAM
         ------------------------
         Margaret B.W. Graham As Trustee and not individually



         /S/ MARGUERITE A. PIRET
         -----------------------
         Marguerite A. Piret As Trustee and not individually



         /S/ DAVID D. TRIPPLE
         --------------------
         David D. Tripple As Trustee and not individually



         /S/ STEPHEN K. WEST
         -------------------
         Stephen K. West As Trustee and not individually



         /S/ JOHN WINTHROP
         -----------------
         John Winthrop As Trustee and not individually