Morgan, Lewis & Bockius LLP
One Federal Street
Boston, Massachusetts 02110-1726
Tel: +1.617.341.7700
Fax: +1.617.341.7701
www.morganlewis.com

October 31, 2017

Pioneer Asset Allocation Trust
60 State Street
Boston, Massachusetts 02109

Ladies and Gentlemen:

We have acted as counsel to Pioneer Asset Allocation Trust, a Delaware
statutory trust, in its individual capacity (the "Trust") and on behalf of its
series Pioneer Solutions - Balanced Fund (the "Acquiring 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 October 31, 2017 (the
"Registration Statement"), with respect to the Acquiring Fund's Class A,
Class C, Class R and Class Y shares of beneficial interest (the "Shares") to be
issued in exchange for the assets of each of Pioneer Solutions - Conservative
Fund and Pioneer Solutions - Growth Fund (each, a "Target Fund"), each a series
of the Trust, as described in the Registration Statement (the
"Reorganization"). You have requested that we deliver this opinion 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 State of the State of Delaware, dated
       as of a recent date, as to the existence of the Trust;

    (b)A copy, certified by the Secretary of State of the State of Delaware, of
       the Trust's Certificate of Trust filed with the Secretary of State (the
       "Certificate of Trust");

    (c)A certificate executed by the 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 authorizing the
       Reorganization and the issuance of the Shares on behalf of the Acquiring
       Fund (the "Resolutions");

    (d)a printer's proof, received on October 31, 2017, of the Registration
       Statement; and



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    (e)a copy of the Agreement and Plan of Reorganization to be entered into by
       the Acquiring Fund and each Target Fund in the form included as Exhibit
       A to the Registration Statement referred to in paragraph (d) above (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 for the purposes of
this opinion that (i) 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; (ii) 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; and (iii) that the Declaration, the By-Laws, 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 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.

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, the By-Laws, 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. In
rendering this opinion and giving this consent, we do not admit that we are in



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the category of persons whose consent is required under Section 7 of the
Securities Act of 1933, as amended, or the rules and regulations of the
Securities and Exchange Commission thereunder.

Very truly yours,

/s/ Morgan, Lewis & Bockius LLP