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                                                                   EXHIBIT 10.39

June 14, 2004

Mr. Samuel L. Shanaman
5 Millstone Circle
Andover, MA 01810

Dear Sam:

      This letter will serve to confirm and memorialize the agreement reached
between you and the Board of Directors ("Board") of PolyMedica Corporation
("PolyMedica" or the "Company") upon your transition from Interim Chief
Executive Officer to full-time Chief Executive Officer of the Company pursuant
to the vote of the Board on January 12, 2004.

      As Chief Executive Officer of PolyMedica, you will perform such
management, advisory and related services to and for the Company and its
subsidiaries as may be reasonably requested from time to time by the Board. You
shall report directly to the Board or its designees.

      You shall receive an annualized base salary of $500,000 ("Base Salary")
payable in equal installments pursuant to the Company's customary payroll
policies in force at the time of payment (but in no event less frequently than
monthly), less all required and authorized payroll deductions and state and
federal withholdings. Your Base Salary may be adjusted from time to time in the
sole discretion of the Company's Board or the Compensation Committee of the
Board (the "Compensation Committee").

      You will be eligible for all normal Company benefits offered to senior
executives administered in accordance with Company policy, which presently
include, among other benefits, long-term disability, life insurance, dental and
health insurance and Company holidays. Subject to length of service and other
eligibility requirements, you will be entitled to participate in the Company's
401(k) retirement plan and Employee Stock Purchase Plan.

      You will earn vacation at the rate of six (6) weeks annually.

      You also will be eligible, in the sole discretion of the Compensation
Committee, to receive an annual discretionary bonus equal to 100% of your Base
Salary based upon objectives to be mutually agreed upon by you and the
Compensation Committee.

      As set forth more fully in the Option Agreement dated February 23, 2004
previously provided to you, you received an option to purchase 240,000 shares of
the Company's Common Stock with 60,000 of such shares being fully vested upon
issuance and the remaining 180,000 shares vesting quarterly over the next three
years.

      Pursuant to the Company's customary policies in force at the time of
payment, you shall be promptly reimbursed for all reasonable and necessary
business related expenses incurred in connection with, or related to, the
performance of services under this letter agreement.

      You are also being provided contemporaneously with this letter agreement a
Retention Agreement that sets forth certain rights that you will have in the
event a change in control of the company occurs during the term of your
employment with the Company.

      You hereby acknowledge and reaffirm your obligations under the
Confidential Disclosure Agreement dated November 6, 2001 and acknowledge your
obligations under the Non-Competition and Non-Solicitation Agreement and the
Invention and Non-Disclosure Agreement that you are contemporaneously executing
with this letter agreement (the "Additional Agreements"), all of which shall
survive the termination of this letter agreement.

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Samuel L. Shanaman
June 14, 2004

      Any dispute or controversy arising out of or relating in any way to your
employment with and/or separation from the Company (including, but not limited
to, all claims, demands or actions under any federal, state or local statute or
regulation regarding employment discrimination, and/or all claims, demands or
actions concerning the interpretation, construction, performance or breach of
this letter agreement) shall be settled by arbitration held in Boston,
Massachusetts in accordance with the Rules of the American Arbitration
Association, before an arbitrator who shall have experience in the area of the
matter in dispute. Each party shall bear its own costs and attorneys' fees in
connection with any arbitration pursuant to this paragraph; provided, however,
that this paragraph shall not apply to any dispute or controversy arising out of
or relating in any way to the interpretation, construction, performance or
breach of the Additional Agreements, and no such dispute or controversy shall be
deemed to be arbitrable in the absence of the Board's written agreement.

      Nothing contained in this letter agreement shall preclude you from
devoting incidental and insubstantial amounts of time to activities other than
the business of the Company and which are not inconsistent with the best
interests of the Company.

      This letter agreement contains the entire understanding between you and
the Board with respect to the subject matter addressed in this letter agreement
and supersedes all prior agreements and understandings between you and the Board
with respect to such subject matter; provided that nothing in this letter
agreement shall affect your obligations under the Additional Agreements.

      This letter agreement may not be amended or supplemented except by written
instrument executed by both you and a duly authorized representative of the
Board. No failure to exercise, and no delay in exercising, any right, power or
privilege hereunder shall operate as a waiver thereof. No waiver of any breach
of any provision of this letter agreement shall be deemed to be a waiver of any
preceding or succeeding breach of the same or any other provision.

      The rights and obligations of this letter agreement shall bind and inure
to the benefit of any successor of the Company by reorganization, merger or
consolidation, or any assignee of all or substantially all of the Company's
business and properties.

      This letter agreement shall continue in effect until terminated by vote of
the Board.

                                      Sincerely,

                                      /s/ Marcia J. Hooper
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                                      Marcia J. Hooper
                                      Compensation Committee
                                      Board of Directors, PolyMedica Corporation

ACCEPTED AND AGREED TO:

/s/ Samuel L. Shanaman
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Samuel L. Shanaman

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