CLASS A SHARES DISTRIBUTION PLAN


                            PIONEER CULLEN VALUE FUND


     CLASS A SHARES DISTRIBUTION PLAN, dated as of _____________, 2005, of
PIONEER CULLEN VALUE FUND (the "Fund"), a series of Pioneer Series Trust III, a
Delaware statutory trust, (the "Trust").


                                   WITNESSETH

     WHEREAS, the Trust is engaged in business as an open-end management
investment company and is registered under the Investment Company Act of 1940,
as amended (collectively with the rules and regulations promulgated thereunder,
the "1940 Act");


     WHEREAS, the Trust intends to distribute shares of beneficial interest (the
"Class A Shares") of the Fund in accordance with Rule 12b-l promulgated by the
Securities and Exchange Commission under the 1940 Act ("Rule 12b- 1"), and
desires to adopt this Class A distribution plan (the "Class A Plan") as a plan
of distribution pursuant to Rule 12b-1;


     WHEREAS, the Trust desires that Pioneer Funds Distributor, Inc., a
Massachusetts corporation ("PFD"), provide certain distribution services for the
Fund's Class A Shares in connection with the Class A Plan;

     WHEREAS, the Trust has entered into an underwriting agreement with PFD,
whereby PFD provides facilities and personnel and renders services to the Fund
in connection with the offering and distribution of the Fund's Class A Shares
(the "Underwriting Agreement");

     WHEREAS, the Trust also recognizes and agrees that (a) PFD may retain the
services of firms or individuals to act as dealers or wholesalers (collectively,
the "Dealers") of the Class A Shares in connection with the offering of Class A
Shares, (b) PFD may compensate any Dealer that sells Class A Shares in the
manner and at the rate or rates to be set forth in an agreement between PFD and
such Dealer and (c) PFD may make such payments to the Dealers for distribution
services out of the fee paid to PFD hereunder, any deferred sales charges
imposed by PFD in connection with the repurchase of Class A Shares, its profits
or any other source available to it;


     WHEREAS, the Board of Trustees of the Trust, in considering whether the
Fund should adopt and implement this Class A Plan, has evaluated such
information as it deemed necessary to an informed determination whether this
Class A Plan should be adopted and implemented and has considered such pertinent
factors as it deemed necessary to form the basis for a decision to use assets of
the Fund for such purposes, and has determined that there is a reasonable
likelihood that the adoption and implementation of this Class A Plan will
benefit the Fund and its Class A shareholders;


     NOW, THEREFORE, the Board of Trustees of the Trust hereby adopts this Class
A Plan for the Fund as a plan of distribution of Class A Shares in accordance
with Rule 12b-l, on the following terms and conditions:





     1. The Fund may expend pursuant to this Class A Plan amounts not to exceed
0.25% of 1% of the average daily net assets attributable to Class A Shares of
the Fund per annum.

     2. Subject to the limit in paragraph 1, the Fund shall reimburse PFD for
amounts expended by PFD to finance any activity which is primarily intended to
result in the sale of Class A Shares of the Fund or the provision of services to
Class A shareholders of the Fund, including but not limited to commissions or
other payments to Dealers and salaries and other expenses of PFD relating to
selling or servicing efforts, provided, that the Board of Trustees of the Trust
shall approve categories of expenses for which reimbursement shall be made
pursuant to this paragraph 2 and, without limiting the generality of the
foregoing, the initial categories of such expenses shall be (i) a service fee to
be paid to qualified broker-dealers in an amount not to exceed 0.25% per annum
of the Fund's daily net assets attributable to Class A Shares; (ii)
reimbursement to PFD for its expenditures for broker-dealer commissions and
employee compensation on certain sales of the Fund's Class A Shares with no
initial sales charge; and (iii) reimbursement to PFD for expenses incurred in
providing services to Class A shareholders and supporting broker-dealers and
other organizations, such as banks and trust companies, in their efforts to
provide such services (any addition of such categories shall be subject to the
approval of the Qualified Trustees, as defined below, of the Trust). Such
reimbursement shall be paid ten (10) days after the end of the month or quarter,
as the case may be, in which such expenses are incurred. The Fund acknowledges
that PFD will charge an initial sales load or a contingent sales load in
connection with certain sales of Class A Shares of the Fund and that PFD will
reallow to Dealers all or a portion of such sales loads, as described in the
Fund's Prospectus from time to time. Nothing contained herein is intended to
have any effect whatsoever on PFD's ability to charge any such sales loads or to
reallow all or any portion thereof to Dealers.


     3. The Trust understands that agreements between PFD and Dealers may
provide for payment of fees to Dealers in connection with the sale of Class A
Shares and the provision of services to Class A shareholders of the Fund.
Nothing in this Class A Plan shall be construed as requiring the Fund to make
any payment to any Dealer or to have any obligations to any Dealer in connection
with services as a dealer of the Class A Shares. PFD shall agree and undertake
that any agreement entered into between PFD and any Dealer shall provide that
such Dealer shall look solely to PFD for compensation for its services
thereunder and that in no event shall such Dealer seek any payment from the Fund
or the Trust.


     4. Nothing herein contained shall be deemed to require the Fund to take any
action contrary to its Agreement and Declaration of Trust, as it may be amended
or restated from time to time, or By-Laws or any applicable statutory or
regulatory requirement to which it is subject or by which it is bound, or to
relieve or deprive the Trust's Board of Trustees of the responsibility for and
control of the conduct of the affairs of the Trust.


     5. This Class A Plan shall become effective upon approval by (i) a vote of
the Board of Trustees, and (ii) a vote of a majority of the Trustees who are not
"interested persons" of the Trust and who have no direct or indirect financial
interest in the operation of the Class A Plan or in any agreement related to the
Class A Plan (the "Qualified Trustees"), such votes to be cast in person at a
meeting called for the purpose of voting on this Class A Plan.

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     6. This Class A Plan will remain in effect indefinitely, provided that such
continuance is "specifically approved at least annually" by a vote of both a
majority of the Trustees of the Trust and a majority of the Qualified Trustees.
If such annual approval is not obtained, this Class A Plan shall expire on the
annual anniversary of the adoption of the Class A Plan following the last such
approval.

     7. This Class A Plan may be amended at any time by the Board of Trustees,
provided that this Class A Plan may not be amended to increase materially the
limitation on the annual percentage of average net assets which may be expended
hereunder without the approval of holders of a "majority of the outstanding
voting securities" of Class A of the Fund and may not be materially amended in
any case without a vote of a majority of both the Trustees and the Qualified
Trustees. Any amendment of this Class A Plan to increase or modify the expense
categories initially designated by the Trustees in paragraph 2 above shall only
require approval of a majority of the Trustees and the Qualified Trustees if
such amendment does not include an increase in the expense limitation set forth
in paragraph 1 above. This Class A Plan may be terminated at any time by a vote
of a majority of the Qualified Trustees or by a vote of the holders of a
"majority of the outstanding voting securities" of the Fund.


     8. In the event of termination or expiration of this Class A Plan, the Fund
may nevertheless, within twelve (12) months of such termination or expiration
reimburse any expense which it incurs prior to such termination or expiration,
provided that payments by the Fund during such twelve-month period shall not
exceed 0.25% of the Fund's average daily net assets attributable to Class A
Shares during such period and provided further that such payments are
specifically approved by the Board of Trustees, including a majority of the
Qualified Trustees.

     9. The Fund and PFD shall provide to the Trust's Board of Trustees, and the
Board of Trustees shall review, at least quarterly, a written report of the
amounts expended under this Class A Plan and the purposes for which such
expenditures were made.


     10. While this Class A Plan is in effect, the selection and nomination of
Qualified Trustees shall be committed to the discretion of the Trustees who are
not "interested persons" of the Trust.

     11. For the purposes of this Class A Plan, the terms "interested persons,"
"majority of the outstanding voting securities" and "specifically approved at
least annually" are used as defined in the 1940 Act.

     12. The Trust shall preserve copies of this Class A Plan, and each
agreement related hereto and each report referred to in paragraph 9 hereof
(collectively, the "Records"), for a period of not less than six (6) years from
the end of the fiscal year in which such Records were made and, for a period of
two (2) years, each of such Records shall be kept in an easily accessible place.

     13. This Class A Plan shall be governed by and construed in accordance with
the laws of The Commonwealth of Massachusetts and the applicable provisions of
the 1940 Act.

     14. If any provision of this Class A Plan shall be held or made invalid by
a court decision, statute, rule or otherwise, the remainder of the Plan shall
not be affected thereby.

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