Filed Number: 33-34801
                                                Filed Pursuant to Rule 497(e) of
                                                      the Securities Act of 1933

                                                               September 4, 2008

                           Pioneer Mid Cap Value Fund

                         Supplement to the March 1, 2008
                 Class A, Class B and Class C Shares Prospectus



Pioneer Mid Cap Value Fund, a U.S. domiciled fund, is no longer available for
public distribution in Germany, Austria and Switzerland.

The Fund was deregistered in Germany, Austria and Switzerland as of
September 30, 2007. Prior to the deregistration, only Class A Shares of the
Fund were available to German, Austrian and Swiss investors.

This German courtesy translation of the prospectus is intended only as
information for current German, Austrian and Swiss investors in the Fund and is
not intended for use by any other parties. Please note that in case of
discrepancies between the English language prospectus and the German
translation, the English version of the prospectus prevails.













                                         (C)2008 Pioneer Funds Distributor, Inc.
                                            Underwriter of Pioneer mutual funds,
                                                                     Member SIPC