Exhibit (11)


                               February 13, 2009


Pioneer Fund
60 State Street
Boston, Massachusetts 02109


Ladies and Gentlemen:

     We have acted as counsel to Pioneer Fund, a Delaware statutory trust, in
its individual capacity (the "Trust"), and on behalf of its series Pioneer Fund
(the "Surviving Fund"), in connection with the Trust's Registration Statement
on Form N-14 to be filed with the Securities and Exchange Commission on or
about February 13, 2009 (the "Registration Statement"), with respect to the
Surviving Fund's Class A shares, Class C shares and Class Y shares (the
"Shares") of beneficial interest to be issued in exchange for the common shares
of Regions Morgan Keegan Select Core Equity Fund, a series of Regions Morgan
Keegan Select Funds, a Massachusetts business trust, as described in the
Registration Statement (the "Merger"). You have requested that we deliver this
opinion to you in connection with the Trust's filing of the Registration
Statement.

     In connection with the furnishing of this opinion, we have examined the
following documents:

     (a) a certificate of the Secretary of the State of Delaware as to the
existence of the Trust;

     (b) a copy, certified by the Secretary of the State of Delaware, of the
Trust's Certificate of Trust dated April 2, 1996 filed with the Secretary of
State (the "Certificate of Trust");

     (c) a certificate executed by the Assistant Secretary of the Trust,
certifying as to, and attaching copies of, the Trust's Agreement and Declaration
of Trust (the "Declaration"), the Trust's By-Laws (the "By-Laws"), and the
resolutions adopted by the Trustees of the Trust at a meeting held on August 29,
2008, authorizing the Merger and the issuance of the Shares on behalf of the
Surviving Fund (the "Resolutions");

     (d) a printer's proof, received on February 12, 2009, of the Registration
Statement; and

     (e) a copy of the form of Agreement and Plan of Reorganization to be
entered into by the Surviving Fund (the "Agreement and Plan of Reorganization").

     In such examination, we have assumed the genuineness of all signatures,
the conformity to the originals of all of the documents reviewed by us as
copies, including conformed copies, the authenticity and completeness of all
original documents reviewed by us in original or copy form and the legal
competence of each individual executing any document. We have assumed that the
Registration Statement as filed with the Securities and Exchange Commission
will be in substantially the form of the printer's proof referred to in
paragraph (d) above, and that the Agreement and Plan of Reorganization will be
duly completed, executed and delivered by the parties thereto in substantially
the form of the copy referred to in paragraph (e) above. We have also assumed
for the purposes of this opinion that the Declaration, the Certificate of
Trust, the Resolutions and the Agreement and Plan of Reorganization will not
have been amended, modified or withdrawn and will be in full force and effect
on the date of issuance of such Shares.

     This opinion is based entirely on our review of the documents listed above
and such other documents as we have deemed necessary or appropriate for the
purposes of this opinion and such investigation of law as we have deemed
necessary or appropriate. We have made no other review or investigation of any
kind whatsoever, and we have assumed, without independent inquiry, the accuracy
of the information set forth in such documents.

     This opinion is limited solely to the Delaware Statutory Trust Act (which
for this purpose includes applicable provisions of the Delaware Constitution
and reported judicial decisions interpreting these laws) to the extent that the
same may apply to or govern the transactions referred to herein, and we express
no opinion with respect to the laws of any other jurisdiction or to any other
laws of the State of Delaware. Further, we express no opinion as to any state
or federal securities laws, including the securities laws of the State of
Delaware. No opinion is given herein as to the choice of law or internal
substantive rules of law which any tribunal may apply to such transaction. In
addition, to the extent that the Declaration or the By-Laws refer to,
incorporate or require compliance with, the Investment Company Act of 1940, as
amended, or any other law or regulation applicable to the Trust, except for the
Delaware Statutory Trust Act, as aforesaid, we have assumed compliance by the
Trust with such Act and such other laws and regulations.

     Our opinion below, as it relates to the nonassessability of the shares of
the Trust, is qualified to the extent that any shareholder is, was or may
become a named Trustee of the Trust.


     We understand that all of the foregoing assumptions and limitations are
acceptable to you.

     Based upon and subject to the foregoing, please be advised that it is our
opinion that the Shares, when issued and sold in accordance with the
Declaration and the Resolutions and for the consideration described in the
Agreement and Plan of Reorganization, will be validly issued, fully paid and
nonassessable.

     This opinion is given as of the date hereof and we assume no obligation to
update this opinion to reflect any changes in law or any other facts or
circumstances which may hereafter come to our attention. We hereby consent to
the filing of this opinion as an exhibit to the Registration Statement.

                                 Very truly yours,



                                 BINGHAM McCUTCHEN LLP