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                                                                   EXHIBIT 14.01

                                 Acusphere, Inc.

                       Code of Business Conduct and Ethics
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                            A MESSAGE FROM THE BOARD

      At Acusphere, Inc. (the "Company"), we believe that conducting business
ethically is critical to our long-term success. Ethics, integrity and honesty
are the foundations upon which we build our reputation and our competitive
excellence.

      We expect every director, officer and employee to practice the highest
standards of conduct in every business relationship - within the Company and
with our customers, business partners, vendors and competitors.

      It is important that each officer, director and employee of the Company
clearly understands and abides by the Company's commitment to ethics, integrity
and honesty. We must comply with applicable laws, rules and regulations in all
aspects of our operations. Our steadfast commitment to the highest professional
standards is essential to our continued success.

      To that end, the Nominating and Corporate Governance Committee of the
Company has recommended, and the Board of Directors of the Company has adopted,
this Code of Business Conduct and Ethics.

                                  INTRODUCTION

      This Code of Business Conduct and Ethics (the "Code") applies to all
directors, officers and employees of the Company and its subsidiaries. The
Company has designed this Code to deter wrongdoing and to promote:

      -     honest and ethical conduct by everyone associated with the Company,
            including the ethical handling of actual or apparent conflicts of
            interest between personal and professional relationships;

      -     full, fair, accurate, timely and understandable disclosure in
            reports and documents that the Company files with, or submits to,
            the United States Securities and Exchange Commission and in the
            Company's other public communications;

      -     compliance with applicable governmental laws, rules and regulations;

      -     the prompt internal reporting of any violations of this Code to the
            appropriate person at the Company; and

      -     accountability for adherence to the Code.

      The effectiveness of this Code depends in part on the cooperation of all
directors, officers and employees in promptly disclosing to the designated
persons within the Company any conduct believed to violate the standards
described in this Code. The Company has established procedures to ensure that
you may report any suspected violations anonymously. The reporting and
enforcement mechanisms described in the Code are intended to assure prompt and
consistent enforcement of the Code, protection for persons reporting
questionable behavior, clear and objective standards for compliance and a fair
process by which to determine violations.

      The Company seeks to foster a culture of compliance with applicable laws,
rules and regulations and the highest standards of business conduct. Everyone at
the Company shall

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promote this culture of compliance. Suspected violations of this Code or
applicable laws, rules or regulation must be reported, and the Company will take
appropriate steps to investigate them internally. Violators shall be subject to
discipline, as deemed appropriate by the Company in its sole discretion,
including immediate termination.

      This Code is neither a contract nor a comprehensive manual that covers
every situation you might encounter. This Code creates no contractual rights. If
you have any questions about the provisions of this Code, or about how you
should conduct yourself in a particular situation, you should consult your
supervisor or department head; the Company's Compliance Officer, whose identity
is posted at all times on the Company's intranet at http://intranet; or the
Company's outside legal counsel.

                              STANDARDS OF CONDUCT

      You must ensure that any financial, business or other activities in which
you are involved outside the workplace are free of conflicts with your
responsibilities to the Company. A "conflict of interest" may occur when your
private interest in any way interferes - or even appears to interfere - with the
interests of the Company. A conflict situation can arise when a person has
interests that may impair the objective performance of his or her duties to the
Company. Conflicts of interest may also arise when a person (or his or her
family member) receives improper personal benefits as a result of his or her
position in the Company.

      You must disclose any matter that you believe might raise doubt regarding
your ability to act objectively and in the Company's best interest. The
following is a non-exhaustive list of examples of situations involving potential
conflicts of interest that should be disclosed:

      -     any Company loan to any employee, officer or director, or Company
            guarantee of any personal obligation;

      -     employment by or acting independently as a consultant to a Company
            competitor, customer or supplier;

      -     directing Company business to any entity in which an employee or
            close family member has a substantial interest;

      -     owning, or owning a substantial interest in, any Company competitor,
            customer or supplier;

      -     using Company assets, intellectual property or other resources for
            personal gain; and

      -     accepting anything of more than nominal value - such as gifts,
            discounts or compensation - from an individual or entity that does
            or seeks to do business with the Company.

      Directors and officers shall disclose any actual or apparent conflict
situation to the Compliance Officer and to the Nominating and Corporate
Governance and Audit Committee (the members of which committees are posted at
all times on the Company's intranet at http://intranet). Employees who are not
officers shall disclose all such situations of which they are aware to an
appropriate supervisor or department head, or to the Compliance Officer. All

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supervisors and department heads who receive such reports must forward them
promptly to the Compliance Officer.

      Members of the Company's Board of Directors must obtain approval from the
Board of Directors before accepting any position as an officer or director of
any outside business concern or entity that has a business relationship with the
Company, or that now is or foreseeably is expected to become a competitor of the
Company.

      The Company's officers and employees must obtain necessary approvals
before accepting (i) any position as an officer or director of an outside
business concern, or (ii) any position as an officer or director with a
not-for-profit entity if there is or may be a Company business relationship with
the entity or an expectation of financial or other support from the Company. The
Company's officers must obtain such approvals from the Nominating and Corporate
Governance Committee; other employees must obtain such approvals from the
Compliance Officer.

      Directors, officers and employees who have obtained such approvals must
promptly notify the appropriate persons specified above in the event of any
change in the nature of such business concern's or entity's relationship with
the Company or if such concern or entity later becomes a competitor of the
Company.

      CORPORATE OPPORTUNITIES

      You owe a duty to the Company to advance its legitimate interests. Thus
you may not (i) take for yourself corporate opportunities that are discovered
through the use of Company property, information or position, without first
offering such opportunities to the Company; (ii) use corporate property,
information or position for personal gain; or (iii) compete with the Company.

      The Company's directors and officers must adhere to their fundamental
duties of good faith, due care and loyalty owed to all shareholders, and to act
at all times with the Company's and its shareholders' best interests in mind.

      CONFIDENTIALITY

      You must maintain the confidentiality of sensitive business, technical or
other information entrusted to you by the Company, its customers or business
partners, except when disclosure is authorized or legally mandated. Confidential
information includes all non-public information that might be of use to
competitors or harmful to the Company, its customers or business partners if
disclosed. This obligation is in addition to the requirements of any
confidentiality agreement that you may have entered into with the Company.

      FAIR DEALING

      You must act fairly, honestly and in good faith in any dealings on behalf
of the Company with any of its customers, suppliers, competitors, employees and
all others. You may not take unfair advantage of anyone through manipulation,
concealment, abuse of privileged information, misrepresentation of material
facts or any other unfair-dealing practice.

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      PROTECTION AND PROPER USE OF COMPANY ASSETS

      You must protect and seek to ensure the efficient use of Company assets.
You should protect against the improper disclosure, theft or misuse of the
Company's intellectual and physical property.

      Company assets should be used only for the Company's legitimate business
purposes. The content of the Company's electronic communication infrastructure
(e-mail, voicemail, Internet access) is not protected by any right of personal
privacy, and the Company can access and monitor it at any time without notice.

      COMPLIANCE WITH LAWS, RULES AND REGULATIONS

      The Company is committed to compliance with applicable laws, rules and
regulations. The Company also maintains separate, detailed policies regarding
such matters as insider trading, fair employment practices and sexual harassment
that can be obtained through Human Resources or the Company Compliance Officer.

      Each and every director, officer and employee must comply with the law.
Questions or concerns about compliance issues should be raised by any of the
means indicated under "Reporting and Enforcement Mechanisms" below.

      FULL, FAIR, ACCURATE, TIMELY AND UNDERSTANDABLE DISCLOSURES

      The Company strives to ensure that all business records and financial
reports are accurate, complete, understandable and not misleading. The Company
is committed to complying with applicable laws requiring the fair and timely
disclosure of material information and ensuring the accuracy of publicly
disseminated information. To that end, the Company maintains internal controls
and procedures designed to provide reasonable assurance of: the safeguarding and
proper management of the Company's assets; the reliability of its financial
reporting in compliance with generally accepted accounting principles; and
compliance with applicable laws and regulations. The Company is committed to
maintaining disclosure controls and procedures designed to ensure that financial
and non-financial information is collected, analyzed and timely reported in full
compliance with applicable law.

      If you obtain information causing you to believe that the Company's books
or records are not being maintained, or that its financial condition or results
of operations are not being disclosed, in accordance with these controls and
procedures, you must report the matter directly by any of the means indicated
under "Reporting and Enforcement Mechanisms" below.

                      REPORTING AND ENFORCEMENT MECHANISMS

      Among every director's, officer's and employee's most important
responsibilities in this Company are the obligations to (1) comply with this
Code and all applicable laws, rules and regulations, and (2) promptly report any
situation or conduct you believe may constitute a possible violation of the Code
or the law.

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      If you should learn of a potential or suspected violation of the Code, you
have an obligation to promptly report the relevant information to one of the
persons listed below. You may address questions about ethics issues and raise
any concerns about a possible violation of the Code or applicable law to:

      -     a supervisor or department head;

      -     the Company's Compliance Officer; and/or

      -     inside or outside Company legal counsel.

      Frequently, a supervisor or department head will be in the best position
to resolve the issue quickly. However, you may also raise any question or
concern with any of the other persons listed above. You may do so orally or in
writing and, if preferred, anonymously.

      If the issue or concern relates to the internal accounting controls of the
Company or any auditing matter, you may report it anonymously to any member of
the Audit Committee of the Board of Directors, the Company's internal Disclosure
Committee (the members of which are posted at all times on the Company's
intranet at http://intranet) or the Compliance Officer, pursuant to the
procedures established by the Audit Committee.

                           POLICY AGAINST RETALIATION

      The Company will not tolerate retaliation in any form against any person
who in good faith reports suspected violations of the Code or any laws, rules or
regulations, voices other ethical concerns, or who is involved on the Company's
behalf in investigating or helping to resolve any such issue. Anyone found to
have retaliated against another employee for any such conduct may be subject to
discipline, including immediate termination. If you believe you have been
subjected to such retaliation, you should report the situation as soon as
possible to the Compliance Officer, the Human Resources Department, or to
Company legal counsel.

                            PENALTIES FOR VIOLATIONS

      The Company is committed to taking prompt and consistent action in
response to violations of this Code. Any covered person who violates the Code is
subject to disciplinary action, including immediate termination. The Company
will promptly investigate reports of suspected violations. It will evaluate
suspected violations on a case-by-case basis and apply an appropriate sanction,
including, in its sole discretion, reporting the violation to authorities.

                                WAIVER/AMENDMENTS

      Only the Board of Directors may waive application of or amend any
provision of this Code. A request for such a waiver should be submitted in
writing to the Board of Directors, or a Committee of the Board of Directors
designated for this purpose, for its consideration. The Company will promptly
disclose to investors all substantive amendments to the Code, as well as all
waivers of the Code granted to directors or officers, including the reasons for
such waivers.

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                RECEIPT OF CODE OF BUSINESS CONDUCT AND ETHICS

      I have received a copy of the Company's Code of Business Conduct and
Ethics (the "Code") and acknowledge I have read and understand its contents. I
understand my obligation to comply with this Code and with the law, and my
obligation to promptly report to appropriate personnel within the Company any
and all suspected violations of this Code or of applicable laws, rules or
regulations. I understand that the Company expressly prohibits any director,
officer or employee from retaliating against any other such person for reporting
suspected violations of the Code or of any laws, rules or regulations. I am
familiar with all the resources that are available if I have questions about
specific conduct, Company policies or applicable laws, rules or regulations.

      If I am an employee, I further understand that the Company is an "at-will"
employer and that employment with the Company is not for a fixed term or
definite period and may be terminated at the will of either party, at any time,
with or without prior notice. I understand that nothing contained in this Code
may be construed as creating a promise of future benefits or a binding contract
with the Company for benefits or for any other purpose.

Printed Name: ______________________________________________


Signature: __________________________________________________


Position: ___________________________________________________


Date: ______________________________________________________



Please sign and date this receipt and return it to Human Resources on behalf of
the Compliance Officer.