Expense Limit and Reimbursement Agreement

         Expense Limit and Reimbursement Agreement made as of August 3, 2004,
between Pioneer Investment Management, Inc. ("PIM") and Pioneer Ibbotson Asset
Allocation Series (the `Trust"), on behalf of each of its series listed on Annex
A (each a "Fund").

         Whereas PIM wishes to reduce the expenses of each Fund until
August 31, 2005; and

         Whereas the Trust on behalf of each Fund wishes to have PIM enter into
such an agreement and is prepared to repay such expenses if a Fund subsequently
achieves a sufficient level of assets;

         Now therefore the parties agree as follows:

         Section 1. PIM agrees, until August 31, 2005, to limit each Fund's
expenses (the "Expense Limitation") by waiving PIM's fees and/or reimbursing the
Fund for the Fund's ordinary operating expenses so that the total expenses of
the Fund (other than extraordinary expenses, such as litigation, taxes,
brokerage commissions, etc.) with respect to Class A shares do not exceed the
percentage of average daily net assets attributable to Class A shares as set
forth on Annex A. PIM also agrees to waive its fees and/or reimburse the
Fund-wide expenses attributable to any other authorized class of shares to the
same extent that such expenses are reduced for Class A shares. In no event,
shall Pioneer Funds Distributor, Inc. be required to waive or PIM reimburse any
fees payable under the Fund's Rule 12b-1 plans. This expense limitation applies
solely to the direct expenses incurred by a Fund and does not apply to or
otherwise limit the expenses incurred by any investment company in which a Fund
may invest.

         Section 2. PIM may terminate or modify the Expense Limitation only in
accordance with this Agreement. PIM agrees that the Expense Limitation shall not
be modified or terminated from the time this Agreement is executed through
August 31, 2005. PIM shall be entitled to modify or terminate the Expense
Limitation with respect to any fiscal year that commences subsequent to August
31, 2005 if, but only if, PIM elects to modify or terminate the Expense
Limitation with respect to such subsequent fiscal year and such election is made
prior to the effective date of the Fund's post-effective amendment to its
Registration Statement on Form N-1A to incorporate the Fund's financial
statements; provided that this Agreement shall remain in effect at all times
until the Fund's then current prospectus is amended or supplemented to reflect
the termination or modification of this Agreement. The election by PIM referred
to in the preceding sentence shall not be subject to the approval of the Fund or
its Board of Trustees, but PIM shall notify the Board of Trustees in advance of
the termination or modification of the Expense Limitation.

         Section 3. PIM shall keep a record of the amount of expenses for each
class of shares that it waived or reimbursed pursuant to Section 1 hereof
("Prior Expenses"). If at any future date the total expenses of the Fund
attributable to a class of shares are less than the Expense Limitation
applicable at the time such expenses were incurred, PIM shall be entitled to be
reimbursed for such Prior Expenses attributable to such class of shares,
provided that such reimbursement does not cause the Fund's expenses attributable
to such class of shares to exceed the Expense Limitation attributable to such
class of shares. If the Fund's expenses with respect to a class of shares
subsequently exceed the Expense Limitation, the reimbursement of Prior Expenses
shall be suspended and, if subsequent reimbursement of Prior Expenses shall be
resumed to the extent that expenses of that class of shares do not exceed the
Expense Limitation (unless previously terminated by PIM), the Expense Limitation
shall be applied. Notwithstanding anything in this Section 3 to the contrary,
the Fund shall not reimburse PIM for any Prior Expense pursuant to this Section
3 more than three (3) years after the expense was incurred.

         Section 4. It is not intended by PIM or the Fund that the reimbursement
agreement in Section 3 shall be an obligation of the Fund unless and until the
total expenses of the Fund attributable to a class of shares are less than the
Expenses Limitation applicable to such class. PIM understands that such total
expenses may never be reduced to such level and there is no assurance that the
Prior Expenses shall be reimbursed. In addition, the Fund shall have the right
to terminate this Agreement, including its obligation to reimburse Prior
Expenses, at any time upon notice to PIM. This Agreement automatically
terminates without obligation by the Fund upon termination of the Management
Contract between PIM and the Fund.

         Section 5. This Agreement shall be governed by the laws of the State of
Delaware.

         In witness whereof, the parties hereto have caused this Agreement to be
signed as of the 3rd day of August, 2004.


PIONEER IBBOTSON ASSET ALLOCATION SERIES     PIONEER INVESTMENT MANAGEMENT, INC.



By:   /s/ Osbert M. Hood                     By: /s/ Dorothy E. Bourassa
                        ------------
      Osbert M. Hood                         Dorothy E. Bourassa
      Executive Vice President               Secretary













Annex A

Pioneer Ibbotson Moderate Allocation Fund
Class A Expense Limit - 0.90% of average daily net assets

Pioneer Ibbotson Growth Allocation Fund
Class A Expense Limit - 0.93% of average daily net assets

Pioneer Ibbotson Aggressive Allocation Fund
Class A Expense Limit - 0.93% of average daily net assets