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                                                                   Exhibit 10.28

                                                                  EXECUTION COPY

                                 ACUSPHERE, INC.

                            INDEMNIFICATION AGREEMENT

         This Indemnification Agreement (the "Agreement") is made as of August
__, 2002, by and between Acusphere, Inc., a Delaware corporation (the
"Company"), and _____________ (the "Indemnitee").

         WHEREAS, in order to continue to attract and retain sophisticated and
experienced individuals to serve on its board of directors, the Company desires
to provide, independent from the indemnification to which the Indemnitee is
otherwise entitled by law and under the Company's Certificate of Incorporation,
as amended and in effect from time to time (the "Charter"), and By-Laws, as
amended and in effect from time to time (the "By-Laws"), indemnification to the
Indemnitee and advances of expenses, all as set forth in this Agreement to the
maximum extent permitted by law;

         NOW, THEREFORE, to induce the Indemnitee to continue to serve the
Company and in consideration of these premises and the mutual agreements set
forth in this Agreement, as well as other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the Company and the
Indemnitee hereby agree as follows:

         1. INDEMNIFICATION.

                  (a) Third Party Proceedings. The Company shall indemnify
Indemnitee if Indemnitee is or was a party or is threatened to be made a party
to any threatened, pending or completed action, suit or proceeding, whether
civil, criminal, administrative or investigative (other than an action by or in
the right of the Company) by reason of the fact that Indemnitee is or was a
director, officer, employee or agent of the Company, or of any subsidiary of the
Company, or by reason of the fact that Indemnitee is or was serving at the
request of the Company as a director, officer, employee or agent of another
corporation, partnership, joint venture, trust or other enterprise, against
expenses (including attorneys' fees), judgments, fines and amounts paid in
settlement (if such settlement is approved in advance by the Company, which
approval shall not be unreasonably withheld or delayed) actually and reasonably
incurred by Indemnitee in connection with such action, suit or proceeding if
Indemnitee acted in good faith and in a manner Indemnitee reasonably believed to
be in or not opposed to the best interests of the Company, and, with respect to
any criminal action or proceeding, had no reasonable cause to believe
Indemnitee's conduct was unlawful. The termination of any action or proceeding
by judgment, order, settlement, conviction, or upon a plea of nolo contendere or
its equivalent, shall not, of itself, create a presumption that Indemnitee did
not act in good faith and in a manner which Indemnitee reasonably believed to be
in or not opposed to the best interests of the Company, and, with respect to any
criminal action or proceeding, had reasonable cause to believe that Indemnitee's
conduct was unlawful.

                  (b) Proceedings by or in the Right of the Company. The Company
shall indemnify Indemnitee if Indemnitee was or is a party or is threatened to
be made a party to any threatened, pending or completed action or suit by or in
the right of the Company or of any
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subsidiary of the Company to procure a judgment in its favor by reason of the
fact that Indemnitee is or was a director, officer, employee or agent of the
Company, or of any subsidiary of the Company, or by reason of the fact that
Indemnitee is or was serving at the request of the Company as a director,
officer, employee or agent of another corporation, partnership, joint venture,
trust or other enterprise, against expenses (including attorneys' fees) actually
and reasonably incurred by Indemnitee in connection with the defense or
settlement of such action or suit if Indemnitee acted in good faith and in a
manner Indemnitee reasonably believed to be in or not opposed to the best
interests of the Company, except that no indemnification shall be made in
respect of any claim, issue or matter as to which Indemnitee shall have been
finally adjudged to be liable to the Company unless and only to the extent that
the Delaware Court of Chancery or any other court in which such action or suit
is or was brought shall determine upon application that, despite the
adjudication of liability but in view of all the circumstances of the case,
Indemnitee is fairly and reasonably entitled to indemnity for such expenses
which the Court of Chancery or other such court shall deem proper.

                  (c) Mandatory Payment of Expenses. To the extent that
Indemnitee has been successful on the merits or otherwise in defense of any
action, suit or proceeding referred to in Section 1(a) or Section 1(b) or in
defense of any claim, issue or matter therein, Indemnitee shall be indemnified
against expenses (including attorneys' fees) actually and reasonably incurred by
Indemnitee in connection therewith.

         2. EXPENSES; INDEMNIFICATION PROCEDURE.

                  (a) Advancement of Expenses. The Company shall advance all
expenses incurred by Indemnitee in connection with the investigation, defense,
settlement or appeal of any civil or criminal action, suit or proceeding
referenced in Section 1(a) or Section 1(b) hereof (but not amounts actually paid
in settlement of any such action or proceeding). Indemnitee hereby undertakes to
repay such amounts advanced if, and to the extent that, it shall ultimately be
determined that Indemnitee is not entitled to be indemnified by the Company as
authorized hereby. The advances to be made hereunder shall be paid by the
Company to Indemnitee within twenty (20) days following receipt by the Company
of a written request of the Indemnitee, but only if the Company has first
received an undertaking (the "Undertaking"), substantially in the form attached
hereto as Exhibit 1, by or on behalf of the Indemnitee to repay the amount of
any such advance if and to the extent that it shall ultimately be determined
that the Indemnitee is not entitled to indemnification for such amount. The
Undertaking shall be unsecured and shall bear no interest and shall be accepted
without reference to the financial ability of the Indemnitee to make repayment.

                  (b) Notice/Cooperation by Indemnitee. Indemnitee shall, as a
condition precedent to his or her right to be indemnified under this Agreement,
give the Company notice in writing as soon as practicable of any claim made
against Indemnitee for which indemnification is or will be sought under this
Agreement. Notice to the Company shall be directed to the Chief Executive
Officer of the Company at the address shown on the signature page of this
Agreement (or such other address as the Company shall designate in writing to
Indemnitee). Notice shall be deemed received three (3) business days after the
date postmarked if sent by domestic certified or registered mail, properly
addressed; otherwise notice shall be deemed received when such
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notice shall actually be received by the Company. In addition, Indemnitee shall
give the Company such information and cooperation as it may reasonably require
and as shall be within Indemnitee's power.

                  (c) Procedure. Any indemnification and advances provided for
in Section 1 and this Section 2 shall be made promptly, and in any event within
forty-five (45) days following receipt by the Company of a written request of
the Indemnitee (or within twenty (20) days in the case of advances made pursuant
to Section 2(a)), unless with respect to such requests the Company reasonably
determines within such applicable period that the Indemnitee did not meet the
applicable standard of conduct or that indemnification is not required under
Section 7 below, or unless otherwise ordered by a court. Such determination
shall be made in each instance by: (a) the board of directors by a majority vote
of a quorum consisting of directors of the Company who were not parties to such
action, suit or proceeding in question ("disinterested directors"); (b) if such
quorum is not obtainable, or even if obtainable if a quorum of disinterested
directors so directs, by independent legal counsel (who may be regular counsel
to the Company) in a written opinion; or (c) by the stockholders of the Company.
If a claim under this Agreement, under any statute, or under any provision of
the Company's Charter or By-Laws providing for indemnification, is not paid in
full by the Company within the applicable period, Indemnitee may bring an action
against the Company to recover the unpaid amount of the claim and Indemnitee
shall also be entitled to be paid for the expenses (including attorneys' fees)
of bringing such action, subject to Section 12 of this Agreement, or unless it
shall ultimately be determined that Indemnitee is not entitled to be indemnified
by the Company as authorized hereby or thereby. It shall be a defense to any
such action that Indemnitee has not met the standards of conduct which make it
permissible under applicable law or this Agreement for the Company to indemnify
Indemnitee for the amount claimed, but the burden of proving such defense shall
be on the Company and Indemnitee shall be entitled to receive interim payments
of expenses pursuant to Section 2(a) unless and until such defense may be
finally adjudged. It is the parties' intention that if the Indemnitee brings any
such action, the question of Indemnitee's right to indemnification shall
ultimately be for the court to decide, and neither the failure of the Company
(including its Board of Directors, any committee or subgroup of the Board of
Directors, independent legal counsel, or its stockholders) to have made a
determination that indemnification of Indemnitee is proper in the circumstances
because Indemnitee has met the applicable standard of conduct required by
applicable law, nor an actual determination by the Company (including its Board
of Directors, any committee or subgroup of the Board of Directors, independent
legal counsel, or its stockholders) that Indemnitee has not met such applicable
standard of conduct, shall create a presumption that Indemnitee has or has not
met the applicable standard of conduct.

                  (d) Notice to Insurers. If, at the time of the receipt of a
notice of a claim pursuant to Section 2(b) hereof, the Company has director and
officer liability insurance in effect, the Company shall give prompt notice of
the commencement of such proceeding to the insurers in accordance with the
procedures set forth in the respective policies. The Company shall thereafter
take all necessary or desirable action to cause such insurers to pay, on behalf
of the Indemnitee, all amounts payable as a result of such proceeding in
accordance with the terms of such policies.
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                  (e) Assumption of Defense and Selection of Counsel. In the
event the Company shall be obligated under Section 2(a) hereof to pay the
expenses of any proceeding against Indemnitee, the Company, if appropriate,
shall be entitled to assume the defense of such proceeding, with counsel
approved by Indemnitee, which approval shall not be unreasonably withheld, upon
the delivery to Indemnitee of written notice of its election so to do.
Notwithstanding the foregoing, the Company shall not be permitted to settle any
action or claim on behalf of Indemnitee in any manner which would impose any
unindemnified liability or penalty on the Indemnitee or require any
acknowledgment of wrongdoing on the part of Indemnitee without Indemnitee's
written consent, which consent shall not be unreasonably withheld. After
delivery of such notice, approval of such counsel by Indemnitee and the
retention of such counsel by the Company, and notwithstanding anything to the
contrary contained herein, the Company will not be liable to Indemnitee under
this Agreement for any fees of counsel subsequently incurred by Indemnitee with
respect to the same proceeding, provided that (i) Indemnitee shall have the
right to employ his or her counsel in any such proceeding at Indemnitee's
expense; and (ii) if (A) the employment of separate counsel by Indemnitee has
been previously authorized by the Company, (B) Indemnitee shall have reasonably
concluded that there may be a conflict of interest between the Company and
Indemnitee in the conduct of any such defense, or (C) the Company shall not, in
fact, have employed counsel to assume the defense of such proceeding, then the
fees and expenses of Indemnitee's counsel shall be at the expense of the
Company. The Company shall not be entitled, without the consent of the
Indemnitee, to assume the defense of any claim brought by or in the right of the
Company or as to which counsel for the Indemnitee shall have reasonably made the
conclusion provided for in clause (ii)(B) above.

         3. ADDITIONAL INDEMNIFICATION RIGHTS; NONEXCLUSIVITY.

                  (a) Scope. Notwithstanding any other provision of this
Agreement, the Company hereby agrees to indemnify the Indemnitee to the fullest
extent permitted by the General Corporation Law of the State of Delaware (the
"DGCL"), notwithstanding that such indemnification is not specifically
authorized by the other provisions of this Agreement or the Company's Charter or
By-Laws. In the event of any change, after the date of this Agreement, under the
DGCL which expands the right of a Delaware corporation to indemnify a member of
its board of directors or an officer, such changes shall be, ipso facto, within
the purview of Indemnitee's rights and the Company's obligations under this
Agreement. In the event of any change under the DGCL which narrows the right of
a Delaware corporation to indemnify a member of its Board of Directors or an
officer, such changes, to the extent not otherwise required by such Section or
any successor section shall have no effect on this Agreement or the parties'
rights and obligations hereunder.

                  (b) Nonexclusivity. The indemnification provided by this
Agreement shall not be deemed exclusive of any rights to which Indemnitee may be
entitled under the Company's Charter, its By-Laws, any agreement, any vote of
stockholders or disinterested directors, the DGCL, or otherwise, both as to
action in Indemnitee's official capacity and as to action in another capacity
while holding such office. The indemnification provided under this Agreement
shall continue as to Indemnitee for any action taken or not taken while serving
in an indemnified
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capacity even though s/he may have ceased to serve in any such capacity at the
time of any action, suit or other covered proceeding.

         4. PARTIAL INDEMNIFICATION. If Indemnitee is entitled under any
provision of this Agreement to indemnification by the Company for some or a
portion of the expenses, judgments, fines or penalties actually or reasonably
incurred by him in the investigation, defense, appeal or settlement of any civil
or criminal action or proceeding, but not, however, for the total amount
thereof, the Company shall nevertheless indemnify Indemnitee for the portion of
such expenses, judgments, fines or penalties to which Indemnitee is entitled.

         5. SEVERABILITY. Nothing in this Agreement is intended to require or
shall be construed as requiring the Company to do or fail to do any act in
violation of applicable law. The Company's inability, pursuant to court order,
to perform its obligations under this Agreement shall not constitute a breach of
this Agreement. The provisions of this Agreement shall be severable as provided
in this Section 5. If this Agreement or any portion hereof shall be invalidated
on any ground by any court of competent jurisdiction, then the Company shall
nevertheless indemnify Indemnitee to the fullest extent permitted by any
applicable portion of this Agreement that shall not have been invalidated, and
the balance of this Agreement not so invalidated shall be enforceable in
accordance with its terms.

         6. OFFICER AND DIRECTOR LIABILITY INSURANCE. The Company shall, from
time to time, make the good faith determination whether or not it is practicable
for the Company to obtain and maintain a policy or policies of insurance with
reputable insurance companies providing the officers and directors of the
Company with coverage for losses from wrongful acts, or to ensure the Company's
performance of its indemnification obligations under this Agreement. Among other
considerations, the Company will weigh the costs of obtaining such insurance
coverage against the protection afforded by such coverage. In all policies of
director and officer liability insurance, Indemnitee shall be named as an
insured in such a manner as to provide Indemnitee the same rights and benefits
as are accorded to the most favorably insured of the Company's directors, if
Indemnitee is a director; or of the Company's officers, if Indemnitee is not a
director of the Company but is an officer; or of the Company's key employees, if
Indemnitee is not an officer or director but is a key employee. Notwithstanding
the foregoing, the Company shall have no obligation to obtain or maintain such
insurance if the Company determines in good faith that such insurance is not
reasonably available, if the premium costs for such insurance are
disproportionate to the amount of coverage provided, if the coverage provided by
such insurance is limited by exclusions so as to provide an insufficient
benefit, or if Indemnitee is covered by similar insurance maintained by a
subsidiary or parent of the Company.

         7. EXCEPTIONS. Any other provision herein to the contrary
notwithstanding, the Company shall not be obligated pursuant to the terms of
this Agreement:

                  (a) To indemnify or advance expenses to Indemnitee with
respect to proceedings or claims initiated or brought voluntarily by Indemnitee
and not by way of defense, except with respect to proceedings brought to
establish or enforce a right to indemnification under this Agreement or any
other statute or law or otherwise as required under Section 145 of the DGCL, but
such indemnification or advancement of expenses may be provided by the
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Company in specific cases if the Board of Directors has approved the initiation
or bringing of the suit; or

                  (b) To indemnify Indemnitee for any expenses incurred by
Indemnitee with respect to any proceeding instituted by Indemnitee to enforce or
interpret this Agreement, if a court of competent jurisdiction determines that
each of the material assertions made by Indemnitee in such proceeding was not
made in good faith or was frivolous; or

                  (c) To indemnify Indemnitee for expenses or liabilities of any
type whatsoever (including, but not limited to, judgments, fines, ERISA excise
taxes or penalties, and amounts paid in settlement), but such exception shall
only apply to the extent such expenses or liabilities have been paid directly to
Indemnitee by an insurance carrier under a policy of officers' and directors'
liability insurance; or

                  (d) To indemnify Indemnitee for expenses or the payment of
profits arising from the purchase and sale by Indemnitee of securities in
violation of Section 16(b) of the Securities Exchange Act of 1934, as amended,
or any similar successor statute; or

                  (e) To indemnify Indemnitee for any acts, omissions or
transactions from which a director may not be relieved of liability under the
Company's Charter or By-Laws, or from which a court of competent jurisdiction
determines a director may not be relieved of liability under the DGCL.

         8. CONSTRUCTION OF CERTAIN PHRASES

                  (a) For purposes of this Agreement, references to the
"Company" shall include, in addition to the resulting corporation, any
constituent corporation (including any constituent of a constituent) absorbed in
a consolidation or merger which, if its separate existence had continued, would
have had power and authority to indemnify its directors, officers, and employees
or agents, so that if Indemnitee is or was a director, officer, employee or
agent of such constituent corporation, or is or was serving at the request of
such constituent corporation as a director, officer, employee or agent of
another corporation, partnership, joint venture, trust or other enterprise,
Indemnitee shall stand in the same position under the provisions of this
Agreement with respect to the resulting or surviving corporation as Indemnitee
would have with respect to such constituent corporation if its separate
existence had continued.

                  (b) For purposes of this Agreement, references to "other
enterprises" shall include employee benefit plans; references to "fines" shall
include any excise taxes assessed on Indemnitee with respect to an employee
benefit plan; and references to "serving at the request of the Company" shall
include any service as a director, officer, employee or agent of the Company
which imposes duties on, or involves services by, such director, officer,
employee or agent with respect to an employee benefit plan, its participants, or
beneficiaries; and if Indemnitee acted in good faith and in a manner Indemnitee
reasonably believed to be in the interest of the participants and beneficiaries
of an employee benefit plan, Indemnitee shall be deemed to have acted in a
manner "not opposed to the best interests of the Company" as referred to in this
Agreement.
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         9. EFFECTIVENESS OF AGREEMENT. This Agreement shall be effective as of
the date set forth on the first page and may apply to acts or omissions of
Indemnitee which occurred prior to such date if Indemnitee was an officer,
director, employee or other agent of the Company, or was serving at the request
of the Company as a director, officer, employee or agent of another corporation,
partnership, joint venture, trust or other enterprise, as the time such act or
omission occurred.

         10. NO RIGHTS OF CONTINUED SERVICE. This Agreement shall not impose any
obligation of the Company to continue Indemnitee's service to the Company beyond
any period otherwise required by law or by other agreements or commitments of
the parties, if any.

         11. MISCELLANEOUS.

                  (a) Governing Law. This Agreement and all acts and
transactions pursuant hereto and the rights and obligations of the parties
hereto shall be governed, construed and interpreted in accordance with the laws
of the State of Delaware, without giving effect to principles of conflict of
law.

                  (b) Consent to Jurisdiction. The Company and the Indemnitee
each hereby irrevocably consent to the exclusive jurisdiction of the Court of
Chancery of Delaware for any purpose in connection with any actions or
proceedings which arise out of or relate to this Agreement.

                  (c) Entire Agreement; Enforcement of Rights. This Agreement
sets forth the entire agreement and understanding of the parties relating to the
subject matter herein and merges all prior discussions between them. No
modification of or amendment to this Agreement, nor any waiver of any rights
under this Agreement, shall be effective unless in writing signed by the parties
to this Agreement. The failure by either party to enforce any rights under this
Agreement shall not be construed as a waiver of any rights of such party.

                  (d) Construction. This Agreement is the result of negotiations
between, and has been reviewed by, each of the parties hereto and their
respective counsel, if any; accordingly, this Agreement shall be deemed to be
the product of all of the parties hereto, and no ambiguity shall be construed in
favor of or against any one of the parties hereto.

                  (e) Notices. Unless otherwise provided in this Agreement, any
notice, demand or request required or permitted to be given under this Agreement
shall be in writing and shall be deemed sufficient when directed to the Chief
Executive Officer of the Company at the address shown on the signature page of
this Agreement (or such other address as the Company shall designate in writing)
and when delivered personally or three business days after being postmarked, as
certified or registered mail, with postage prepaid, and addressed to the party
to be notified at such party's address as set forth below or as subsequently
modified by written notice.
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                  (f) Counterparts. This Agreement may be executed in two or
more counterparts, each of which shall be deemed an original and all of which
together shall constitute one instrument.

                  (g) Successors And Assigns. This Agreement shall be binding
upon the Company and its successors and assigns and shall inure to the benefit
of Indemnitee and Indemnitee's heirs, legal representatives, executives and
administrators.

                  (h) Subrogation. In the event of payment under this Agreement,
the Company shall be subrogated to the extent of such payment to all of the
rights of recovery of Indemnitee, who shall execute all documents required and
shall do all acts that may be necessary to secure such rights and to enable the
Company to effectively bring suit to enforce such rights.

                  (i) Term. All agreements and obligations of the Company
contained herein shall continue during the period that the Indemnitee is a
director, officer or agent of the Company and shall continue thereafter so long
as Indemnitee shall be subject to any possible claim or threatened, pending or
completed action, suit or proceeding, whether civil, criminal, administrative or
investigative, by reason of the fact that Indemnitee was serving in the capacity
referred to herein.

         12. ATTORNEYS' FEES. In the event that any action is instituted by
Indemnitee under this Agreement to enforce or interpret any of the terms hereof,
and in the event Indemnitee is ultimately successful in such action, Indemnitee
shall be entitled to be paid all court costs and expenses, including reasonable
attorneys' fees, actually and reasonably incurred by Indemnitee with respect to
such action. In the event of an action instituted by or in the name of the
Company under this Agreement or to enforce or interpret any of the terms of this
Agreement, Indemnitee shall be entitled to be paid all court costs and expenses,
including reasonable attorneys' fees, actually and reasonably incurred by
Indemnitee in defense of such action (including with respect to Indemnitee's
counterclaims and cross-claims made in such action), unless the Company is
ultimately successful in such action.

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         IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the date first above written.

ACUSPHERE, INC.

By: ________________________________            __________________________

Name: ______________________________            Indemnitee

Title: _____________________________

Address:  Acusphere, Inc.                       Address: _________________
          500 Arsenal Street
          Watertown, MA  02472                           _________________
          (617) 648-8800 (phone)
          (617) 926-4750 (fax)                           _________________
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Exhibit 1
UNDERTAKING

         1. This Undertaking is submitted pursuant to the Indemnification
Agreement dated as of ________________ between Acusphere, Inc., a Delaware
corporation (the "Company"), and the undersigned (the "Agreement"). Capitalized
terms used but not defined herein shall have the respective meanings set forth
in the Agreement.

         2. I am requesting certain Expense Advances in connection with a Claim.

         3. I hereby undertake to repay such Expense Advances if it shall
ultimately be determined that I am not entitled to be indemnified by the Company
therefor under the Agreement or otherwise.

         4. The Expense Advances are, in general, all related to:





                          Signed: _____________________________

                          Dated: ______________________________