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                                                                Exhibit 99.11(a)

               SULLIVAN & WORCESTER LLP
               1666 K STREET, N.W.
               WASHINGTON, D.C. 20006
               TELEPHONE: 202-775-1200
               FACSIMILE: 202-293-2275

1290 AVENUE OF THE AMERICAS         ONE POST OFFICE SQUARE
29th FLOOR                          BOSTON, MASSACHUSETTS 02109
NEW YORK, NEW YORK 10104            TELEPHONE: 617-338-2800
TELEPHONE: 212-660-3000             FACSIMILE: 617-338-2880
FACSIMILE: 212-660-3001

                                        September 18, 2003


Touchstone Variable Series Trust
221 East Fourth Street
Suite 300
Cincinnati, Ohio 45202

Ladies and Gentlemen:

     We have been requested by Touchstone Variable Series Trust, a Massachusetts
business trust with transferable shares (the "Trust") established under an
Agreement and Declaration of Trust dated February 7, 1994, as amended (the
"Declaration"), for our opinion with respect to certain matters relating to the
Touchstone Enhanced Dividend 30 Fund (currently known as Touchstone Enhanced 30
Fund) (the "Acquiring Fund"), a series of the Trust. We understand that the
Trust is about to file an amendment to its Registration Statement on Form N-14
(File No. 333-108157) for the purpose of registering shares of the Trust under
the Securities Act of 1933, as amended (the "1933 Act"), in connection with the
proposed acquisition by the Acquiring Fund of all of the assets of Separate
Account Ten of Integrity Life Insurance Company (the "Acquired Account"), in
exchange solely for shares of the Acquiring Fund and the assumption by the
Acquiring Fund of the liabilities of the Acquired Account pursuant to an
Agreement and Plan of Reorganization, the form of which is included in the
Form N-14 Registration Statement (the "Plan").

     We have, as special counsel, participated in various business and other
proceedings relating to the Trust. We have examined copies, either certified or
otherwise proved to be genuine to our satisfaction, of the Trust's Declaration
and By-Laws, and other documents relating to its organization, operation, and
proposed operation, including the proposed Plan, and

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we have made such other investigations as, in our judgment, are necessary or
appropriate to enable us to render the opinion expressed below.

     Based upon the foregoing, and assuming the approval by contractowners of
the Acquired Account of certain matters scheduled for their consideration at
meetings presently anticipated to be held on December 5, 2003 it is our opinion
that the shares of the Acquiring Fund currently being registered, when issued in
accordance with the Plan and the Trust's Declaration and By-Laws, will be
legally issued, fully paid and non-assessable by the Trust, subject to
compliance with the 1933 Act, the Investment Company Act of 1940, as amended,
and applicable state laws regulating the offer and sale of securities. We note,
however, that under certain circumstances, shareholders of the Trust may be held
personally liable for its obligations.

     We hereby consent to the filing of this opinion with and as a part of the
Registration Statement on Form N-14. In giving such consent, we do not thereby
admit that we come within the category of persons whose consent is required
under Section 7 of the 1933 Act or the rules and regulations promulgated
thereunder.

                                                Very truly yours,

                                                /s/SULLIVAN & WORCESTER LLP
                                                ---------------------------
                                                SULLIVAN & WORCESTER LLP