Exhibit 1.1



                                6,422,450 SHARES





                            HARVARD BIOSCIENCE, INC.

                          COMMON STOCK, $.01 PAR VALUE







                             UNDERWRITING AGREEMENT


                           DATED: DECEMBER ____, 2000






                                                          December ____, 2000



Thomas Weisel Partners LLC
Dain Rauscher Incorporated
ING Barings LLC
As Representatives of the several Underwriters
c/o Thomas Weisel Partners LLC
One Montgomery Street, Suite 3700
San Francisco, California  94104



Ladies and Gentlemen:

         INTRODUCTION. Harvard Bioscience, Inc., a Delaware corporation (the
"COMPANY"), proposes, subject to the terms and conditions contained herein, to
issue and sell to the several underwriters named in SCHEDULE A hereto (the
"UNDERWRITERS"), and the stockholder of the Company (the "SELLING STOCKHOLDER")
named in SCHEDULE B hereto severally propose to sell to the several
Underwriters, an aggregate of 6,422,450 shares of the Common Stock, par value
$.01 per share, of the Company (the "FIRM SHARES"), of which 6,250,000 shares
are to be issued and sold by the Company and 172,450 shares are to be sold by
the Selling Stockholder, as set forth opposite such Selling Stockholder's name
in SCHEDULE B hereto.

         The Company also proposes to issue and sell to the several Underwriters
not more than an additional 937,500 shares of its Common Stock, par value $.01
per share (the "ADDITIONAL SHARES"), if and to the extent that you shall have
determined to exercise, on behalf of the Underwriters, the right to purchase
such shares of common stock granted to the Underwriters in Section 3 hereof. The
Firm Shares and the Additional Shares are hereinafter collectively referred to
as the "SHARES". The shares of Common Stock, par value $.01 per share, of the
Company to be outstanding after giving effect to the sales contemplated hereby
are hereinafter referred to as the "COMMON STOCK". The Company and the Selling
Stockholder are hereinafter sometimes collectively referred to as the "SELLERS".
Thomas Weisel Partners LLC, Dain Rauscher Incorporated and ING Barings LLC have
agreed to act as representatives of the several Underwriters (in such capacity,
the "REPRESENTATIVES") in connection with the offering and sale of the Shares.

         The Company has filed with the Securities and Exchange Commission (the
"COMMISSION") a registration statement on Form S-1 (file no. 333-45996),
including a prospectus, relating to the Shares. The registration statement as
amended at the time it becomes effective, including the information (if any)
deemed to be part of the registration statement at the time of effectiveness
pursuant to Rule 430A under the Securities Act of 1933, as amended (the
"SECURITIES ACT"), is hereinafter referred to as the "REGISTRATION STATEMENT".
The prospectus (as described in Rule 434(a)(i) under the Securities Act) in the
form first used to confirm sales of Shares is hereinafter referred to as the
"DISTRIBUTED PROSPECTUS"; the prospectus included in the Registration Statement
at the time of its effectiveness (including the information, if any, deemed to
be a part of the Registration Statement at the time of effectiveness pursuant to
Rule 430A under the Securities Act) is hereinafter referred to as the "FILED
PROSPECTUS"; and the Distributed Prospectus and the Filed Prospectus are
hereinafter referred to collectively as the "PROSPECTUS". If the Company has
filed a registration statement to register additional shares of Common Stock
pursuant to Rule 462(b) under the Securities Act (the "RULE 462


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REGISTRATION STATEMENT"), then any reference herein to the term "REGISTRATION
STATEMENT" shall be deemed to include such Rule 462 Registration Statement. All
references in this Agreement to the Registration Statement, the Rule 462
Registration Statement, a preliminary prospectus, the Prospectus, or any
amendments or supplements to any of the foregoing, shall include any copy
thereof filed with the Commission pursuant to its Electronic Data Gathering,
Analysis and Retrieval System ("EDGAR").

         As part of the offering contemplated by this Agreement, Thomas Weisel
Partners has agreed to reserve out of the Shares set forth opposite its name on
SCHEDULE A to this Agreement, up to 300,000 shares, for sale to the Company's
employees, officers, and directors and other parties associated with the Company
(collectively, "PARTICIPANTS"), as set forth in the Prospectus under the heading
"Underwriting" (the "DIRECTED SHARE PROGRAM"). The Shares to be sold by Thomas
Weisel Partners pursuant to the Directed Share Program (the "DIRECTED SHARES")
will be sold by Thomas Weisel Partners pursuant to this Agreement at the public
offering price. Any Directed Shares not orally confirmed for purchase by any
Participants by the end of the first business day after the date on which this
Agreement is executed will be offered to the public by Thomas Weisel Partners as
set forth in the Prospectus.

         1. REPRESENTATIONS AND WARRANTIES OF THE COMPANY. The Company hereby
represents and warrants to, and agrees with, each of the Underwriters that:

         1.1. EFFECTIVE REGISTRATION STATEMENT. To the Company's knowledge,
based solely on oral advice provided by the Commission on the date hereof, the
Registration Statement has become effective; the Company has not received notice
of any stop order suspending the effectiveness of the Registration Statement,
and the Company has not received notice of any proceedings for such purpose
pending before or, threatened by, the Commission.

         1.2. CONTENTS OF REGISTRATION STATEMENT. (i) The Registration Statement
did not contain and, as amended or supplemented, if applicable, will not, as of
the applicable effective date of the Registration Statement and any amendment
thereto, contain any untrue statement of a material fact or omit to state a
material fact required to be stated therein or necessary to make the statements
therein not misleading, (ii) the Registration Statement and the Prospectus
conform and, as amended or supplemented, if applicable, will conform in all
material respects to the requirements of the Securities Act and the applicable
rules and regulations of the Commission thereunder, and (iii) the Prospectus
does not contain and, as amended or supplemented, if applicable, will not, as of
the applicable date of the Prospectus and any amendment or supplement thereto,
contain any untrue statement of a material fact or omit to state a material fact
necessary to make the statements therein, in the light of the circumstances
under which they were made, not misleading, except that the representations and
warranties set forth in this paragraph do not apply to statements or omissions
in the Registration Statement or the Prospectus based upon information furnished
to the Company in writing by, or on behalf of, any Underwriter through you
expressly for use therein.

         1.3. DUE INCORPORATION. The Company has been duly incorporated, exists
as a corporation in good standing under the laws of the jurisdiction of its
incorporation, has the corporate power and authority to own its property and to
conduct its business as described in the Prospectus and is duly qualified to
transact business and is in good standing in each jurisdiction in which the
conduct of its business or its ownership or leasing of property requires such
qualification, except where the failure to be so qualified or be in good
standing would not have a material adverse effect on the Company and its
subsidiaries, taken as a whole.

         1.4. SUBSIDIARIES. Each subsidiary of the Company has been duly
incorporated, exists as a corporation in good standing under the laws of the
jurisdiction of its incorporation, has the corporate power


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and authority to own its property and to conduct its business as described in
the Prospectus and is duly qualified to transact business and is in good
standing in each jurisdiction in which the conduct of its business or its
ownership or leasing of property requires such qualification, except where the
failure to be so qualified or be in good standing would not have a material
adverse effect on the Company and its subsidiaries, taken as a whole. All of the
issued shares of capital stock of each subsidiary of the Company have been duly
authorized and validly issued, are fully paid and non-assessable and are owned
by the Company, directly or through a wholly-owned subsidiary of the Company,
free and clear of all liens, encumbrances, equities or claims, except as
disclosed in the Prospectus and any liens, encumbrances, equities or claims
placed on the Company's assets generally in the ordinary course of business.

         1.5. UNDERWRITING AGREEMENT. This Agreement has been duly authorized,
executed and delivered by the Company, and is a valid and binding agreement of
the Company, enforceable in accordance with its terms, except as rights to
indemnification hereunder may be limited by applicable law, including federal
and state securities laws and pubic policy considerations and except as the
enforcement hereof may be limited by bankruptcy, insolvency, reorganization,
moratorium or other similar laws relating to or affecting the rights and
remedies of creditors or by general equitable principles.

         1.6. DESCRIPTION OF CAPITAL STOCK. The authorized capital stock of the
Company conforms in all material respects as to legal matters to the description
thereof contained in the Prospectus.

         1.7. AUTHORIZED STOCK. The shares of Common Stock (including the Shares
to be sold by the Selling Stockholder) outstanding prior to the issuance of the
Shares to be sold by the Company have been duly authorized and are validly
issued, fully paid and non-assessable.

         1.8. VALIDLY ISSUED SHARES. The Shares to be sold by the Company have
been duly authorized and, when issued and delivered in accordance with the terms
of this Agreement, will be validly issued, fully paid and non-assessable, and
the issuance of such Shares will not be subject to any preemptive or similar
rights.

         1.9. NO CONFLICT. The execution and delivery by the Company of, and the
performance by the Company of its obligations under, this Agreement will not
contravene any provision of applicable law or the certificate of incorporation
or by-laws of the Company or any agreement or other instrument binding upon the
Company or any of its subsidiaries that is material to the Company and its
subsidiaries, taken as a whole, or any judgment, order or decree of any
governmental body, agency or court having jurisdiction over the Company or any
subsidiary, and no consent, approval, authorization or order of, or
qualification with, any governmental body or agency is required for the
performance by the Company of its obligations under this Agreement, except such
as have been obtained under the Securities Act or the rules and regulations
thereunder and such as may be required by the securities or Blue Sky laws of the
various states or by the by-laws and rules of the National Association of
Securities Dealers, Inc. in connection with the offer and sale of the Shares.

         1.10. NO MATERIAL ADVERSE CHANGE. There has not occurred any material
adverse change in the financial condition, earnings, business or operations of
the Company and its subsidiaries, taken as a whole, from that set forth in the
Prospectus (exclusive of any amendments or supplements thereto subsequent to the
date of this Agreement).

         1.11. LEGAL PROCEEDINGS; EXHIBITS. There are no legal or governmental
proceedings pending or, to the best knowledge of the Company, threatened, to
which the Company or any of its subsidiaries is a party or to which any of the
properties of the Company or any of its subsidiaries is subject


                                       4


that are required to be described in the Registration Statement or the
Prospectus and are not so described or any statutes, regulations, contracts or
other documents that are required to be described in the Registration Statement
or the Prospectus or to be filed as exhibits to the Registration Statement that
are not described or filed as required.

         1.12. COMPLIANCE WITH SECURITIES ACT. Each preliminary prospectus filed
as part of the registration statement as originally filed or as part of any
amendment thereto, or filed pursuant to Rule 424 under the Securities Act,
conformed when so filed in all material respects with the Securities Act and the
applicable rules and regulations of the Commission thereunder, other than with
respect to the omission of pricing and share information in the prospectus
contained in the initially filed Registration Statement.

         1.13. NOT AN INVESTMENT COMPANY. The Company is not and, after giving
effect to the offering and sale of the Shares and the application of the
proceeds thereof as described in the Prospectus, will not be an "investment
company" as such term is defined in the Investment Company Act of 1940, as
amended.

         1.14. COMPLIANCE WITH ENVIRONMENTAL LAWS. The Company and its
subsidiaries (i) are in compliance with any and all applicable foreign, federal,
state and local laws and regulations relating to the protection of human health
and safety, the environment or hazardous or toxic substances or wastes,
pollutants or contaminants ("ENVIRONMENTAL LAWS"), (ii) have received all
permits, licenses or other approvals required of them under applicable
Environmental Laws to conduct their respective businesses and (iii) are in
compliance with all terms and conditions of any such permit, license or
approval, except where such noncompliance with Environmental Laws, failure to
receive required permits, licenses or other approvals or failure to comply with
the terms and conditions of such permits, licenses or approvals would not,
individually or in the aggregate, have a material adverse effect on the Company
and its subsidiaries, taken as a whole.

         1.15. INTENTIONALLY OMITTED

         1.16. NO REGISTRATION RIGHTS. There are no contracts, agreements or
understandings between the Company and any person granting such person the right
to require the Company to file a registration statement under the Securities Act
with respect to any securities of the Company or to require the Company to
include such securities with the Shares registered pursuant to the Registration
Statement other than as described in the Registration Statement and as have been
waived in writing in connection with the offering contemplated hereby (except
with respect to the Shares to be sold by the Selling Stockholder pursuant to
this Agreement).

         1.17. CUBAN BUSINESS STATUTE. The Company has complied with all
provisions of Section 517.075, Florida Statutes relating to doing business with
the Government of Cuba or with any person or affiliate located in Cuba.

         1.18. ABSENCE OF MATERIAL CHARGES. Subsequent to the respective dates
as of which information is given in the Registration Statement and the
Prospectus, (i) the Company and its subsidiaries have not incurred any material
liability or obligation, direct or contingent, nor entered into any material
transaction except such liabilities or obligations incurred, or transactions
entered into, in the ordinary course of business; (ii) the Company has not
purchased any of its outstanding capital stock, nor declared, paid or otherwise
made any dividend or distribution of any kind on its capital stock other than
ordinary and customary dividends; and (iii) there has not been any material
change in the capital stock, short-term debt or long-term debt of the Company
and its subsidiaries, except in each case as described in the Registration
Statement and the Prospectus.


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         1.19. TITLE TO PROPERTIES. The Company and its subsidiaries have good
and marketable title to all real property and valid title to all personal
property described in the Prospectus as owned by them which is material to the
business of the Company and its subsidiaries, in each case free and clear of all
liens, encumbrances and defects except such as are described in the Prospectus
or such as do not materially affect the value of such property and do not
interfere with the use made and proposed to be made of such property by the
Company and its subsidiaries; and any real property and buildings described in
the Prospectus as held under lease by the Company and its subsidiaries are held
by them under valid and subsisting leases enforceable against the Company and,
to the knowledge of the Company, the other parties thereto, with such exceptions
as are described in the Registration Statement or Propsectus or are not material
and do not interfere with the use made and proposed to be made of such property
and buildings by the Company and its subsidiaries.

         1.20. INTELLECTUAL PROPERTY RIGHTS. Except as disclosed in the
Registration Statement and the Prospectus, the Company and its subsidiaries own
or possess, or can acquire on reasonable terms, all material patents, patent
rights, licenses, inventions, copyrights, know-how (including trade secrets and
other unpatented and/or unpatentable proprietary or confidential information,
systems or procedures), trademarks, service marks and trade names necessary to
conduct the business as now conducted by them, and neither the Company nor any
of its subsidiaries has received any notice of infringement of or conflict with
asserted rights of others with respect to any of the foregoing which,
individually or in the aggregate, if the subject of an unfavorable decision,
ruling or finding, would have a material adverse affect on the Company and its
subsidiaries, taken as a whole.

         1.21. NO LABOR DISPUTES. No labor dispute with the employees of the
Company or any of its subsidiaries exists or, to the knowledge of the Company,
is imminent that would have a material adverse effect on the Company and its
subsidiaries, taken as a whole; and the Company is not aware of any existing,
threatened or imminent labor disturbance by the employees of any of its
principal suppliers, manufacturers or contractors that would be reasonably
likely to have a material adverse effect on the Company and its subsidiaries,
taken as a whole.

         1.22. INSURANCE. The Company and its subsidiaries are insured by
insurers of recognized financial responsibility against such losses and risks
and in such amounts as are customary in the businesses in which they are
engaged; and neither the Company nor any of its subsidiaries has any reason to
believe that it will not be able to renew its existing insurance coverage as and
when such coverage expires or to obtain similar coverage from similar insurers
as may be necessary to continue its business at a cost that would not have a
material adverse effect on the Company and its subsidiaries, taken as a whole.

         1.23. GOVERNMENTAL PERMITS. The Company and its subsidiaries possess
all certificates, authorizations and permits necessary to conduct their
respective businesses as presently conducted, and neither the Company nor any of
its subsidiaries has received any notice of proceedings relating to the
revocation or modification of any such certificate, authorization or permit
which, individually or in the aggregate, if the subject of an unfavorable
decision, ruling or finding, would have a material adverse effect on the Company
and its subsidiaries, taken as a whole.

         1.24. ACCOUNTING CONTROLS. The Company and each of its subsidiaries
maintains a system of internal accounting controls sufficient to provide
reasonable assurance that (i) transactions are executed in accordance with
management's general or specific authorizations; (ii) transactions are recorded
as necessary to permit preparation of financial statements in accordance with
generally accepted accounting principles and to maintain asset accountability;
(iii) access to assets is permitted only in accordance with management's


                                       6


general or specific authorization; and (iv) the recorded accountability for
assets is compared with the existing assets at reasonable intervals and
appropriate action is taken with respect to any differences.

         1.25. DIRECTED SHARE PROGRAM. The Company represents and warrants to
Thomas Weisel Partners that, to the knowledge of the Company (i) the
Registration Statement, the Prospectus and any preliminary prospectus comply,
and any further amendments or supplements thereto will comply, with any
applicable laws or regulations of foreign jurisdictions in which the Prospectus
or any preliminary prospectus, as amended or supplemented, if applicable, are
distributed in connection with the Directed Share Program and (ii) no
authorization, approval, consent, license, order, registration or qualification
of or with any government, governmental instrumentality or court, other than
such as have been obtained, is necessary under the securities laws and
regulations of foreign jurisdictions in which the Directed Shares are offered
outside the United States.

         1.26. COMPLIANCE WITH LAWS. To the Company's knowledge, the Company and
each of its subsidiaries is conducting its business in compliance with the Fair
Labor Standards Act, the rules and regulations of the federal Food and Drug
Administration, and all applicable federal, state and local laws, rules and
regulations of the jurisdictions in which it is conducting business, including,
without limitation, all applicable local, state and federal laws and regulations
governing zoning and land use, except where the failure to be so in compliance
would not have a material adverse effect on the Company and its subsidiaries,
taken as a whole.

         2. REPRESENTATIONS AND WARRANTIES OF THE SELLING STOCKHOLDER. The
Selling Stockholder represents and warrants to, and agrees with, each of the
Underwriters that:

         2.1. DUE AUTHORIZATION. This Agreement has been duly authorized,
executed and delivered by or on behalf of such Selling Stockholder and
constitutes a valid and binding obligation of such Selling Stockholder,
enforceable against such Selling Stockholder in accordance with its terms,
except as rights to indemnification hereunder may be limited by applicable
federal or state securities laws and public policy considerations and except as
the enforcement hereof may be limited by bankruptcy, insolvency, reorganization,
moratorium or other similar laws relating to or affecting the rights and
remedies of creditors or by general equitable principles.

         2.2. SELLING STOCKHOLDER DOCUMENTS. The Custody Agreement and the Power
of Attorney have each been duly authorized, executed and delivered by such
Selling Stockholder and each such document constitutes a valid and binding
obligation of such Selling Stockholder enforceable against such Selling
Stockholder in accordance with its respective terms, except as rights to
indemnification thereunder may be limited by applicable federal or state
securities laws and public policy considerations and except as the enforcement
thereof may be limited by bankruptcy, insolvency, reorganization, moratorium or
other similar laws relating to or affecting the rights and remedies of creditors
or by general equitable principles.

         2.3. NO CONFLICT. The execution and delivery by such Selling
Stockholder of, and the performance by such Selling Stockholder of its
obligations under, this Agreement, the Custody Agreement signed by such Selling
Stockholder and Harvard Bioscience, Inc., as Custodian, relating to the deposit
of the Shares to be sold by such Selling Stockholder (the "CUSTODY AGREEMENT")
and the Power of Attorney appointing certain individuals as such Selling
Stockholder's attorneys-in-fact to the extent set forth therein, relating to the
transactions contemplated hereby and by the Registration Statement (the "POWER
OF ATTORNEY") will not contravene any provision of applicable law, or the
certificate of incorporation or by-laws of such Selling Stockholder (if such
Selling Stockholder is a corporation), or any material agreement or other
instrument binding upon such Selling Stockholder or any judgment, order or
decree of any governmental


                                       7


body, agency or court having jurisdiction over such Selling Stockholder, and no
consent, approval, authorization or order of, or qualification with, any
governmental body or agency is required for the performance by such Selling
Stockholder of its obligations under this Agreement or the Custody Agreement or
Power of Attorney of such Selling Stockholder, except such as have been obtained
under the Securities Act or the rules and regulations thereunder and such as may
be required by the securities or Blue Sky laws of the various states or by the
by-laws and rules of the National Association of Securities Dealers, Inc. in
connection with the offer and sale of the Shares.

         2.4. INTENTIONALLY OMITTED

         2.5. GOOD TITLE TO SHARES. Such Selling Stockholder has, and on each
Closing Date will have, valid title to the Shares to be sold by such Selling
Stockholder and full right and power, and all authorization and approval
necessary to enter into this Agreement, the Custody Agreement and the Power of
Attorney and to sell, transfer and deliver the Shares to be sold by such Selling
Stockholder.

         2.6. DELIVERY OF COMMON SHARES. Delivery of the Shares to be sold by
such Selling Stockholder pursuant to this Agreement will pass title to such
Shares free and clear of any security interests, claims, liens and other
encumbrances, except those created by this Agreement or the Custody Agreement.

         2.7. NO REGISTRATION RIGHTS. Such Selling Stockholder does not have any
registration or other similar rights to have any equity or debt securities
registered for sale by the Company under the Registration Statement or included
in the offering contemplated by this Agreement, other than as described in the
Registration Statement and as have been waived in writing in connection with the
offering contemplated hereby.

         2.8. NO PRICE STABILIZATION OR MANIPULATION. Such Selling Stockholder
has not taken and will not take, directly or indirectly, any action designed to
or that might be reasonably expected to cause or result in stabilization or
manipulation of the price of the Common Stock to facilitate the sale or resale
of the Shares.

         2.9. DISCLOSURE BY SELLING STOCKHOLDER IN REGISTRATION STATEMENT. Such
parts of the Registration Statement comprised of the table and the notes thereto
under the caption "Principal and Selling Stockholder" in the form supplied to
the Selling Stockholder which specifically relate to the Selling Stockholder do
not contain any untrue statement of a material fact or omit to state a material
fact required to be stated therein or necessary to make the statements therein
not misleading.

         3. PURCHASE AND SALE AGREEMENTS.

         3.1. FIRM SHARES. Subject to the terms and conditions of this
Agreement, each Seller, severally and not jointly, hereby agrees to sell to the
several Underwriters, and each Underwriter, upon the basis of the
representations and warranties herein contained, agrees, severally and not
jointly, to purchase from such Seller at $______ a share (the "PURCHASE PRICE")
the number of Firm Shares (subject to such adjustments to eliminate fractional
shares as you may determine) that bears the same proportion to the number of
Firm Shares to be sold by such Seller as the number of Firm Shares set forth in
SCHEDULE A hereto opposite the name of such Underwriter bears to the total
number of Firm Shares.

         3.2. ADDITIONAL SHARES. On the basis of the representations and
warranties contained in this Agreement, and subject to its terms and conditions,
the Company agrees to sell to the Underwriters the Additional Shares, and the
Underwriters shall have a one-time right to purchase, severally and not jointly,
up


                                       8


to 937,500 Additional Shares at the Purchase Price per share. If you, on behalf
of the Underwriters, elect to exercise such option, you shall so notify the
Company in writing not later than thirty (30) days after the date of this
Agreement, which notice shall specify the number of Additional Shares to be
purchased by the Underwriters and the date on which such shares are to be
purchased. Such date may be the same as the Closing Date (as defined below) but
not earlier than the Closing Date or, if delivered subsequent to the Closing
Date, three business days after delivery of such notice of the Company, nor
later than ten (10) business days after the date of such notice. Additional
Shares may be purchased as provided in Section 4 hereof solely for the purpose
of covering over-allotments made in connection with the offering of the Firm
Shares. If any Additional Shares are to be purchased, each Underwriter agrees,
severally and not jointly, to purchase the number of Additional Shares (subject
to such adjustments to eliminate fractional shares as you may determine) that
bears the same proportion to the total number of Additional Shares to be
purchased as the number of Firm Shares set forth in SCHEDULE A hereto opposite
the name of such Underwriter bears to the total number of Firm Shares.

         3.3. MARKET STANDOFF PROVISION. The Company hereby agrees that, without
the prior written consent of Thomas Weisel Partners, it will not, during the
period ending 180 days after the date of the Prospectus, (i) offer, pledge,
sell, contract to sell, sell any option or contract to purchase, purchase any
option or contract to sell, grant any option, right or warrant to purchase,
lend, or otherwise transfer or dispose of, directly or indirectly, any shares of
Common Stock or any securities convertible into or exercisable or exchangeable
for Common Stock or (ii) enter into any swap or other arrangement that transfers
to another, in whole or in part, any of the economic consequences of ownership
of the Common Stock, whether any such transaction described in clause (i) or
(ii) above is to be settled by delivery of Common Stock or such other
securities, in cash or otherwise. The foregoing sentence shall not apply to (A)
the Shares to be sold by the Company hereunder, (B) the issuance by the Company
of shares of Common Stock upon the exercise of options or warrants or the
conversion of a security outstanding on the date hereof of which the
Underwriters have been advised in writing or which is described in the
Prospectus, (C) the award of options under the Company's stock plans in the
ordinary course of business consistent with past practices that are not
exercisable within 180 days from the date of the Prospectus or (D) the Company's
issuance of shares of Common Stock in connection with the acquisition by the
Company of another company or entity or any other strategic partnership or other
joint venture, provided that the terms of such issuance contractually prohibit
the resale or other disposition of such shares of Common Stock within 180 days
from the date of the Prospectus. The Selling Stockholder, agrees that, without
the prior written consent of Thomas Weisel Partners, it will not, during the
period ending 180 days after the date of the Prospectus, make any demand for, or
exercise any right with respect to, the registration of any shares of Common
Stock or any security convertible into or exercisable or exchangeable for Common
Stock.

         3.4. TERMS OF PUBLIC OFFERING. The Sellers are advised by you that the
Underwriters propose to make a public offering of their respective portions of
the Shares as soon after the Registration Statement and this Agreement have
become effective as in your judgment is advisable. The Sellers are further
advised by you that the Shares are to be offered to the public initially at
$_____________ a share (the "PUBLIC OFFERING PRICE") and to certain dealers
selected by you at a price that represents a concession not in excess of $______
a share less than the Public Offering Price, and that any Underwriter may allow,
and such dealers may reallow, a concession, not in excess of $_____ a share, to
any Underwriter or to certain other dealers.


                                       9


         4. PAYMENT AND DELIVERY.

         4.1. FIRM SHARES. Payment for the Firm Shares to be sold by each Seller
shall be made to such Seller by wire transfer in immediately available funds
against delivery of such Firm Shares for the respective accounts of the several
Underwriters at 10:00 a.m., New York City time, on December 11, 2000 or at such
other time on the same or such other date, not later than December 12, 2000 as
shall be designated in writing by you. The time and date of such payment are
hereinafter referred to as the "CLOSING DATE".

         4.2. ADDITIONAL SHARES. Payment for any Additional Shares shall be made
to the Company by wire transfer in immediately available funds in New York City
against delivery of such Additional Shares for the respective accounts of the
several Underwriters at 10:00 a.m., New York City time, on the date specified in
the notice described in Section 3.2 or at such other time on the same or on such
other date, in any event not later than January 20, 2001 as shall be designated
in writing by you. The time and date of such payment are hereinafter referred to
as the "OPTION CLOSING DATE".

         4.3. DELIVERY OF CERTIFICATES. Certificates for the Firm Shares and the
Additional Shares, if any, shall be in definitive form and registered in such
names and in such denominations as you shall request in writing not later than
two (2) full business days prior to the Closing Date or the Option Closing Date,
as the case may be. The certificates evidencing the Firm Shares and Additional
Shares shall be delivered to you on the Closing Date or the Option Closing Date,
as the case may be, for the respective accounts of the several Underwriters,
with any transfer taxes payable in connection with the transfer of the Shares to
the Underwriters duly paid, against payment of the Purchase Price therefor.

         5. COVENANTS OF THE COMPANY. In further consideration of the agreements
of the Underwriters herein contained, the Company covenants with each
Underwriter as follows:

         5.1. FURNISH COPIES OF REGISTRATION STATEMENT AND PROSPECTUS. To
furnish to you, without charge, [NUMBER OF REPRESENTATIVES PLUS ONE] copies of
the signed Registration Statement (including exhibits thereto) and for delivery
to each other Underwriter a conformed copy of the Registration Statement
(without exhibits thereto) and to furnish to you in New York City, without
charge, prior to 10:00 a.m. New York City time on the business day next
succeeding the date of this Agreement and during the period mentioned in Section
5.3 below, as many copies of the Prospectus and any supplements and amendments
thereto or to the Registration Statement as you may reasonably request, provided
that copies of any such amendment or supplement made nine months or more after
the issue date of the Prospectus shall be at the expense of the Underwriters.

         5.2. NOTIFICATION OF AMENDMENTS OR SUPPLEMENTS. Before amending or
supplementing the Registration Statement or the Prospectus, to furnish to you a
copy of each such proposed amendment or supplement and not to file any such
proposed amendment or supplement to which you promptly and reasonably object in
writing, and to file with the Commission within the applicable period specified
in Rule 424(b) under the Securities Act any prospectus required to be filed
pursuant to such rule.

         5.3. FILINGS OF AMENDMENTS OR SUPPLEMENTS. If, during such period after
the first date of the public offering of the Shares as in the opinion of counsel
for the Underwriters the Prospectus is required by law to be delivered in
connection with sales by an Underwriter or dealer (the "PROSPECTUS DELIVERY
PERIOD"), any event shall occur or condition exist as a result of which it is
necessary to amend or supplement the Prospectus in order to make the statements
therein, in the light of the circumstances when the Prospectus is delivered to a
purchaser, not misleading, or if, in the opinion of counsel for the
Underwriters, it is


                                       10


necessary to amend or supplement the Prospectus to comply with applicable law,
forthwith to prepare, file with the Commission and furnish, at its own expense,
to the Underwriters and to the dealers (whose names and addresses you will
furnish to the Company) to which Shares may have been sold by you on behalf of
the Underwriters and to any other dealers upon request, either amendments or
supplements to the Prospectus so that the statements in the Prospectus as so
amended or supplemented will not, in the light of the circumstances when the
Prospectus is delivered to a purchaser, be misleading or so that the Prospectus,
as amended or supplemented, will comply with law and in the case any Underwriter
is required by law to deliver a prospectus in connection with sales of any of
the Shares at any time nine months or more after the time of issue of the
Prospectus, upon your request but at the expense of such Underwriter, to prepare
and deliver to such Underwriter as many copies as you may request of an amended
or supplemented Prospectus complying with Section 10(a)(3) of the Securities
Act.

         5.4. BLUE SKY LAWS. To endeavor to qualify the Shares for offer and
sale under the securities or Blue Sky laws of such jurisdictions as you shall
reasonably request.

         5.5. EARNINGS STATEMENT. To make generally available to its
securityholders as soon as practicable, but in any event not later than eighteen
(18) months after the effective date of the Registration Statement (as defined
in Rule 158(c) under the Securities Act), an earnings statement of the Company
and its subsidiaries (which need not be audited) complying with Section 11(a) of
the Securities Act and the rules and regulations thereunder (including, at the
option of the Company, Rule 158).

         5.6. USE OF PROCEEDS. To apply the net proceeds from the sale of the
Shares sold by it in the manner described under the caption "Use of Proceeds" in
the Prospectus.

         5.7. TRANSFER AGENT. To engage and maintain, at its expense, a
registrar and transfer agent for the Common Stock.

         5.8. INTENTIONALLY OMITTED

         5.9. DIRECTED SHARE PROGRAM. That in connection with the Directed Share
Program, the Company will ensure that the Directed Shares will be restricted to
the extent required by the National Association of Securities Dealers, Inc. (the
"NASD") or the NASD rules from sale, transfer, assignment, pledge or
hypothecation for a period of three (3) months following the date of the
effectiveness of the Registration Statement. Thomas Weisel Partners will notify
the Company as to which Participants will need to be so restricted. The Company
will direct the transfer agent to place stop transfer restrictions upon such
securities for such period of time.

         5.10. EXCHANGE ACT COMPLIANCE. During the Prospectus Delivery Period,
the Company will file all documents required to be filed with the Commission
pursuant to Section 13, 14 or 15 of the Exchange Act in the manner and within
the time periods required by the Exchange Act.

         6. CONDITIONS TO CLOSING. The obligations of the Sellers to sell the
Shares to the several Underwriters and the several obligations of the
Underwriters to purchase and pay for the Shares on the Closing Date are subject
to the following conditions:

         6.1. EFFECTIVE REGISTRATION STATEMENT. The Registration Statement shall
have become effective not later than 4:30 p.m. (New York City time) on the date
hereof.


                                       11


         6.2. RULE 462 REGISTRATION STATEMENT. If the Company elects to rely
upon Rule 462(b), the Company shall file a Rule 462 Registration Statement with
the Commission in compliance with Rule 462(b) within the applicable time period
prescribed for such filing by the rules and regulations of the Securities Act,
and the Company shall at the time of filing either pay to the Commission the
filing fee for the Rule 462 Registration Statement or give irrevocable
instructions for the payment of such fee pursuant to Rule 111(b) under the
Securities Act.

         6.3. PROSPECTUS FILED WITH COMMISSION. The Company shall have filed the
Prospectus with the Commission (including the information required by Rule 430A
under the Securities Act) in the manner and within the time period required by
Rule 424(b) under the Securities Act; or the Company shall have filed a
post-effective amendment to the Registration Statement containing the
information required by such Rule 430A, and such post-effective amendment shall
have become effective; or, if the Company elected to rely upon Rule 434 under
the Securities Act and obtained the Representatives' consent thereto, the
Company shall have filed a term sheet with the Commission in the manner and
within the time period required by such Rule 424(b).

         6.4. NO STOP ORDER. No stop order suspending the effectiveness of the
Registration Statement, any Rule 462 Registration Statement, or any
post-effective amendment to the Registration Statement, shall be in effect and
no proceedings for such purpose shall have been initiated or threatened by the
Commission.

         6.5. INTENTIONALLY OMITTED

         6.6. INTENTIONALLY OMITTED

         6.7. NO MATERIAL ADVERSE CHANGE. There shall not have occurred any
change in the financial condition or in the earnings, business or operations of
the Company and its subsidiaries, taken as a whole, from that set forth in the
Prospectus (exclusive of any amendments or supplements thereto subsequent to the
date of this Agreement) that, in the reasonable judgment of the Representatives,
is material and adverse and that makes it, in the reasonable judgment of the
Representatives, impracticable to market the Shares on the terms and in the
manner contemplated in the Prospectus.

         6.8. OFFICER'S CERTIFICATE. The Underwriters shall have received on the
Closing Date a certificate, dated the Closing Date and signed by the Chief
Executive Officer or President of the Company, to the effect that the statements
set forth in Sections 6.4 and 6.7 and to the effect that the representations and
warranties of the Company contained in this Agreement are true and correct as of
the Closing Date and that the Company has complied with all of the agreements
and satisfied all of the conditions on its part to be performed or satisfied
hereunder on or before the Closing Date.

         6.9. OPINION OF COMPANY COUNSEL. The Underwriters shall have received
on the Closing Date an opinion of Goodwin, Procter & Hoar LLP, counsel for the
Company, dated the Closing Date, the form of which is attached hereto as EXHIBIT
A. The opinion shall be rendered to the Underwriters at the request of the
Company and shall so state therein.

         6.10. OPINION OF SELLING STOCKHOLDERS' COUNSEL. The Underwriters shall
have received on the Closing Date an opinion of Goodwin, Procter & Hoar LLP,
counsel for the Selling Stockholder, dated the Closing Date, the form of which
is attached hereto as EXHIBIT B. The opinion shall be rendered to the
Underwriters at the request of the Selling Stockholder and shall so state
therein.


                                       12


         6.11. OPINION OF PATENT COUNSEL. The Underwriters shall have received
on the Closing Date an opinion of Hale & Dorr LLP, patent counsel for the
Company, dated the Closing Date, the form of which is attached hereto as EXHIBIT
C. The opinion shall be rendered to the Underwriters at the request of the
Company and shall so state therein.

         6.12. OPINION OF UNDERWRITERS COUNSEL. The Underwriters shall have
received on the Closing Date an opinion of Mintz, Levin, Cohn, Ferris, Glovsky
and Popeo, P.C., counsel for the Underwriters, dated the Closing Date, covering
the matters referred to in EXHIBIT A, paragraph (9) (but only as to the
statements in the Prospectus under "Description of Capital Stock" and
"Underwriters") and (14). With respect to paragraph (14) of EXHIBIT A, such
counsel may state that their opinion and belief are based upon their
participation in the preparation of the Registration Statement and Prospectus
and any amendments or supplements thereto and review and discussion of the
contents thereof, but are without independent check or verification, except as
specified.

         6.13. ACCOUNTANT'S COMFORT LETTER. The Underwriters shall have
received, on each of the date hereof and the Closing Date, a letter dated the
date hereof or the Closing Date, as the case may be, in form and substance
reasonably satisfactory to the Underwriters, from KPMG LLP, independent public
accountants, containing statements and information of the type ordinarily
included in accountants' "comfort letters" to underwriters with respect to the
financial statements and certain financial information contained in the
Registration Statement and the Prospectus; PROVIDED that the letter delivered on
the Closing Date shall use a "cut-off date" not earlier than the date hereof.

         6.14. LOCK-UP AGREEMENTS. The "lock-up" agreements, each substantially
in the form of EXHIBIT D hereto, between you and certain stockholders, officers
and directors of the Company, shall have been executed and delivered to you on
or before the date hereof.

         6.15. SELLING STOCKHOLDER'S CERTIFICATE. The Underwriters shall have
received on the Closing Date a certificate, dated the Closing Date and signed by
or on behalf of such Selling Stockholder, to the effect that the representations
and warranties of the Selling Stockholder contained in this Agreement are true
and correct as of the Closing Date and that the Selling Stockholder has complied
with all of the agreements and satisfied all of the conditions on his part to be
performed or satisfied hereunder on or before the Closing Date.

         6.16. SELLING STOCKHOLDER DOCUMENTS. On the date hereof, the Company
and the Selling Stockholder shall have furnished for review by the
Representatives copies of the Powers of Attorney and Custody Agreements executed
by each of the Selling Stockholder and such further information, certificates
and documents as the Representatives may reasonably request.

         6.17. ADDITIONAL DOCUMENTS. On the Closing Date, the Representatives
and counsel for the Underwriters shall have received such information, documents
and opinions as they may reasonably require for the purposes of enabling them to
pass upon the issuance and sale of the Shares as contemplated herein, or in
order to evidence the accuracy of any of the representations and warranties, or
the satisfaction of any of the conditions or agreements, herein contained.

         The several obligations of the Underwriters to purchase Additional
Shares hereunder are subject to the satisfaction of each of the above conditions
on or prior to the Option Closing Date and to the delivery to you on the Option
Closing Date of such documents as you may reasonably request with respect to the
good standing of the Company, the due authorization and issuance of the
Additional Shares and other matters related to the issuance of the Additional
Shares.


                                       13


         7. EXPENSES. Whether or not the transactions contemplated in this
Agreement are consummated or this Agreement is terminated, the Company agrees to
pay or cause to be paid all expenses incident to the performance of its
obligations under this Agreement, including: (i) the fees, disbursements and
expenses of the Company's counsel, the Company's accountants and counsel for the
Selling Stockholder in connection with the registration and delivery of the
Shares under the Securities Act and all other fees or expenses incurred in
connection with the preparation and filing of the Registration Statement, any
preliminary prospectus, the Prospectus and amendments and supplements to any of
the foregoing, including all printing costs associated therewith, and the
mailing and delivering of copies thereof to the Underwriters and dealers, in the
quantities hereinabove specified, (ii) all costs and expenses related to the
transfer and delivery of the Shares to the Underwriters, including any transfer
or other taxes payable thereon, (iii) the reasonable costs of printing or
producing any Blue Sky or legal investment memorandum in connection with the
offer and sale of the Shares under state securities laws and all expenses in
connection with the qualification of the Shares for offer and sale under state
securities laws as contemplated by Section 5.4 hereof, including filing fees and
the reasonable fees and disbursements of counsel for the Underwriters in
connection with such qualification and in connection with the Blue Sky or legal
investment memorandum, (iv) all filing fees and the reasonable fees and
disbursements of counsel to the Underwriters incurred in connection with the
review and qualification of the offering of the Shares by the NASD, (v) all fees
and expenses in connection with the preparation and filing of the registration
statement on Form 8-A relating to the Common Stock and all costs and expenses
incident to listing the Shares on the Nasdaq National Market, (vi) the cost of
printing certificates representing the Shares, (vii) the costs and charges of
any transfer agent, registrar or depositary, (viii) the costs and expenses of
the Company relating to investor presentations on any "road show" undertaken in
connection with the marketing of the offering of the Shares, including, without
limitation, expenses associated with the production of road show slides and
graphics, fees and expenses of any consultants engaged in connection with the
road show presentations with the prior approval of the Company, travel and
lodging expenses of the representatives and officers of the Company and any such
consultants, (ix) all expenses in connection with any offer and sale of the
Shares outside of the United States, including filing fees and the reasonable
fees and disbursements of counsel for the Underwriters in connection with offers
and sales outside of the United States, (x) all reasonable fees and
disbursements of counsel incurred by the Underwriters in connection with the
Directed Share Program and stamp duties, similar taxes or duties or other taxes,
if any, incurred by the Underwriters in connection with the Directed Share
Program and (xi) all other costs and expenses incident to the performance of the
obligations of the Company hereunder for which provision is not otherwise made
in this Section. It is understood, however, that except as provided in this
Section, Section 8 entitled "Indemnity and Contribution", and the last paragraph
of Section 11 below, the Underwriters will pay all of their costs and expenses,
including fees and disbursements of their counsel, stock transfer taxes on
resale of any of the Shares by them and any advertising expenses connected with
any offers they may make.

         The provisions of this Section shall not supersede or otherwise affect
any agreement that the Sellers may otherwise have for the allocation of such
expenses among themselves.

         8. INDEMNITY AND CONTRIBUTION.

         8.1. INDEMNIFICATION OF THE UNDERWRITERS. The Company agrees to
indemnify and hold harmless each Underwriter and each person, if any, who
controls any Underwriter within the meaning of either Section 15 of the
Securities Act or Section 20 of the Exchange Act, from and against any and all
losses, claims, damages and liabilities (including, without limitation, any
legal or other expenses reasonably incurred in connection with defending or
investigating any such action or claim) (a) caused by any untrue statement or
alleged untrue statement of a material fact contained in the Registration
Statement or any amendment thereof, any preliminary prospectus or the Prospectus
(as amended or supplemented if the Company shall have


                                       14


furnished any amendments or supplements thereto), or (b) caused by any omission
or alleged omission to state therein a material fact required to be stated
therein or necessary to make the statements therein, in the case of any
preliminary prospectus or the Prospectus in light of the circumstances under
which they were made, not misleading, except (i) insofar as such losses, claims,
damages or liabilities are caused by any such untrue statement or omission or
alleged untrue statement or omission based upon information furnished to the
Company in writing by or on behalf of any Underwriter expressly for use therein
and (ii) that with respect to any preliminary prospectus, the foregoing
indemnity agreement shall not inure to the benefit of any Underwriter from whom
the person asserting any loss, claim, damage or liability purchased Shares, or
any person controlling such Underwriter, if copies of the Prospectus were timely
delivered to the Underwriter pursuant to Section 5 and a copy of the Prospectus
(as then amended or supplemented if the Company shall have furnished any
amendments or supplements thereto) was not sent or given by or on behalf of such
Underwriter to such person, if required by law so to have been delivered, at or
prior to the written confirmation of the sale of the Shares to such person, and
if the Prospectus (as so amended or supplemented) would have cured the defect
giving rise to such loss, claim, damage, liability or expense.

         8.2. INTENTIONALLY OMITTED

         8.3. INDEMNIFICATION OF UNDERWRITERS BY THE SELLING STOCKHOLDER. The
Selling Stockholder agrees to indemnify and hold harmless each Underwriter and
each person, if any, who controls any Underwriter within the meaning of either
Section 15 of the Securities Act or Section 20 of the Exchange Act, from and
against any and all losses, claims, damages and liabilities (including, without
limitation, any legal or other expenses reasonably incurred in connection with
defending or investigating any such action or claim) caused by any untrue
statement or alleged untrue statement of a material fact contained in the
Registration Statement or any amendment thereof, any preliminary prospectus or
the Prospectus (as amended or supplemented if the Company shall have furnished
any amendments or supplements thereto), or caused by any omission or alleged
omission to state therein a material fact required to be stated therein or
necessary to make the statements therein, in the case of any preliminary
prospectus or the Prospectus in light of the circumstances under which they were
made, not misleading, but only with reference to information relating to such
Selling Stockholder furnished in writing by or on behalf of such Selling
Stockholder expressly for use in the Registration Statement, any preliminary
prospectus, the Prospectus or any amendments or supplements thereto, except that
with respect to any preliminary prospectus, the foregoing indemnity agreement
with respect to the preliminary prospectus shall not inure to the benefit of any
Underwriter from whom the person asserting any loss, claim, damage or liability
purchased Shares, or any person controlling such Underwriter, if copies of the
Prospectus were timely delivered to the Underwriter pursuant to Section 5 and a
copy of the Prospectus (as then amended or supplemented if the Company shall
have furnished any amendments or supplements thereto) was not sent or given by
or on behalf of such Underwriter to such person, if required by law to have been
so delivered, at or prior to the written confirmation of the sale of the Shares
to such person, and if the Prospectus (as so amended or supplemented) would have
cured the defect giving rise to such loss, claim, damage, liability or expense.
In no event shall the Selling Stockholder be liable or responsible for
indemnification or any other cause of action under this Agreement for any amount
in the aggregate in excess of the net proceeds received by the Selling
Stockholder with respect to the Shares sold by the Selling Stockholder.

         8.4. INDEMNIFICATION BY THE UNDERWRITERS. Each Underwriter agrees,
severally and not jointly, to indemnify and hold harmless the Company, the
Selling Stockholder, each of the directors of the Company, each of the officers
of the Company who sign the Registration Statement and each person, if any, who
controls the Company or any Selling Stockholder within the meaning of either
Section 15 of the Securities Act or Section 20 of the Exchange Act from and
against any and all losses, claims, damages and liabilities (including, without
limitation, any legal or other expenses reasonably incurred in connection with


                                       15


defending or investigating any such action or claim) caused by any untrue
statement or alleged untrue statement of a material fact contained in the
Registration Statement or any amendment thereof, any preliminary prospectus or
the Prospectus (as amended or supplemented if the Company shall have furnished
any amendments or supplements thereto), or caused by any omission or alleged
omission to state therein a material fact required to be stated therein or
necessary to make the statements therein, in the case of the Preliminary
prospectus or the Prospectus in light of the circumstances under which they were
made, not misleading, but only with reference to information furnished to the
Company in writing by or on behalf of such Underwriter expressly for use in the
Registration Statement, any preliminary prospectus, the Prospectus or any
amendments or supplements thereto.

         8.5. INDEMNIFICATION PROCEDURES. In case any proceeding (including any
governmental investigation) shall be instituted involving any person in respect
of which indemnity may be sought pursuant to this Section 8, such person (the
"INDEMNIFIED PARTY") shall promptly notify the person against whom such
indemnity may be sought (the "INDEMNIFYING PARTY") in writing and the
indemnifying party, upon request of the indemnified party, shall retain counsel
reasonably satisfactory to the indemnified party to represent the indemnified
party and any others the indemnifying party may designate in such proceeding and
shall pay the fees and disbursements of such counsel related to such proceeding.
In any such proceeding, any indemnified party shall have the right to retain its
own counsel, but the fees and expenses of such counsel shall be at the expense
of such indemnified party unless (i) the indemnifying party and the indemnified
party shall have mutually agreed to the retention of such counsel or (ii) the
named parties to any such proceeding (including any impleaded parties) include
both the indemnifying party and the indemnified party and representation of both
parties by the same counsel would be inappropriate due to actual or potential
differing interests between them. It is understood that the indemnifying party
shall not, in respect of the legal expenses of any indemnified party in
connection with any proceeding or related proceedings in the same jurisdiction,
be liable for (i) the fees and expenses of more than one separate firm (IN
ADDITION TO ANY LOCAL COUNSEL) for all Underwriters and all persons, if any, who
control any Underwriter within the meaning of either Section 15 of the
Securities Act or Section 20 of the Exchange Act, (ii) the fees and expenses of
more than one separate firm (in addition to any local counsel) for the Company,
its directors, its officers who sign the Registration Statement and each person,
if any, who controls the Company within the meaning of either such Section and
(iii) the fees and expenses of more than one separate firm (in addition to any
local counsel) for all Selling Stockholder and all persons, if any, who control
any Selling Stockholder within the meaning of either such Section, and that all
such fees and expenses shall be reimbursed as they are incurred. In the case of
any such separate firm for the Underwriters and such control persons of any
Underwriters, such firm shall be designated in writing by Thomas Weisel
Partners. In the case of any such separate firm for the Company, and such
directors, officers and control persons of the Company, such firm shall be
designated in writing by the Company. In the case of any such separate firm for
the Selling Stockholder and such control persons of any Selling Stockholder,
such firm shall be designated in writing by the persons named as
attorneys-in-fact for the Selling Stockholder under the Powers of Attorney. The
indemnifying party shall not be liable for any settlement of any proceeding
effected without its written consent, but if settled with such consent or if
there be a final judgment for the plaintiff, the indemnifying party agrees to
indemnify the indemnified party from and against any loss or liability by reason
of such settlement or judgment. Notwithstanding the foregoing sentence, if at
any time an indemnified party shall have requested an indemnifying party to
reimburse the indemnified party for fees and expenses of counsel as contemplated
by the second and third sentences of this paragraph, the indemnifying party
agrees that it shall be liable for any settlement of any proceeding effected
without its written consent if (i) such settlement is entered into more than 30
days after receipt by such indemnifying party of the aforesaid request and (ii)
such indemnifying party shall not have reimbursed the indemnified party in
accordance with such request prior to the date of such settlement. No
indemnifying party shall, without the prior written consent of the indemnified
party, effect any settlement of any pending or threatened proceeding in respect
of which any indemnified party is or could have been a party and indemnity


                                       16


could have been sought hereunder by such indemnified party, unless such
settlement includes an unconditional release of such indemnified party from all
liability on claims that are the subject matter of such proceeding.

         Notwithstanding anything contained herein to the contrary, if indemnity
may be sought pursuant to Section 8.6 hereof in respect of such action or
proceeding, then in addition to such separate firm for the indemnified parties,
the indemnifying party shall be liable for the reasonable fees and expenses of
not more than one separate firm (IN ADDITION TO ANY LOCAL COUNSEL) for Thomas
Weisel Partners for the defense of any losses, claims, damages and liabilities
arising out of the Directed Share Program, and all persons, if any, who control
Thomas Weisel Partners within the meaning of either Section 15 of the Act or
Section 20 of the Exchange Act.

         8.6. INDEMNIFICATION FOR DIRECTED SHARE PROGRAM. The Company agrees to
indemnify and hold harmless Thomas Weisel Partners and each person, if any, who
controls Thomas Weisel Partners within the meaning of either Section 15 of the
Securities Act or Section 20 of the Exchange Act ("THOMAS WEISEL PARTNERS
ENTITIES"), from and against any and all losses, claims, damages and liabilities
(including, without limitation, any legal or other expenses reasonably incurred
in connection with defending or investigating any such action or claim) (i)
caused by any untrue statement or alleged untrue statement of a material fact
contained in the prospectus wrapper material prepared by or with the consent of
the Company for distribution in foreign jurisdictions in connection with the
Directed Share Program attached to the Prospectus or any preliminary prospectus,
or caused by any omission or alleged omission to state therein a material fact
required to be stated therein or necessary to make the statement therein, when
considered in conjunction with the Prospectus or any applicable preliminary
prospectus, not misleading; (ii) caused by the failure of any Participant to pay
for and accept delivery of the shares which, immediately following the
effectiveness of the Registration Statement, were subject to a properly
confirmed agreement to purchase; or (iii) related to, arising out of, or in
connection with the Directed Share Program, provided that, the Company shall not
be responsible under this subparagraph (iii) for any losses, claim, damages or
liabilities (or expenses relating thereto) that are finally judicially
determined to have resulted from the bad faith or gross negligence of Thomas
Weisel Partners Entities. Thomas Weisel Partners hereby agrees in connection
with any losses, claims, damages or liabilities for which indemnification is
sought pursuant to Section 8.6(ii) or (iii) above, that it shall act in good
faith and in a reasonable commercial manner to mitigate any such losses, claims,
damages and liabilities.

         8.7. CONTRIBUTION AGREEMENT. To the extent the indemnification provided
for in this Section 8 is unavailable to an indemnified party or insufficient in
respect of any losses, claims, damages or liabilities referred to therein, then
each indemnifying party under such paragraph, in lieu of indemnifying such
indemnified party thereunder, shall contribute to the amount paid or payable by
such indemnified party as a result of such losses, claims, damages or
liabilities (or actions in respect thereof) (i) in such proportion as is
appropriate to reflect the relative benefits received by the indemnifying party
or parties on the one hand and the indemnified party or parties on the other
hand from the offering of the Shares or (ii) if the allocation provided by
clause 8.7(i) above is not permitted by applicable law, in such proportion as is
appropriate to reflect not only the relative benefits referred to in clause
8.7(i) above but also the relative fault of the indemnifying party or parties on
the one hand and of the indemnified party or parties on the other hand in
connection with the statements or omissions that resulted in such losses,
claims, damages or liabilities (or actions in respect thereof), as well as any
other relevant equitable considerations. The relative benefits received by the
Sellers on the one hand and the Underwriters on the other hand in connection
with the offering of the Shares shall be deemed to be in the same respective
proportions as the net proceeds from the offering of the Shares (before
deducting expenses) received by each Seller and the total underwriting discounts
and commissions received by the Underwriters, in each case as set forth in the
table on the cover of


                                       17


the Prospectus, bear to the aggregate Public Offering Price of the Shares. The
relative fault of the Sellers on the one hand and the Underwriters on the other
hand shall be determined by reference to, among other things, whether the untrue
or alleged untrue statement of a material fact or the omission or alleged
omission to state a material fact relates to information supplied by the Sellers
or by the Underwriters and the parties' relative intent, knowledge, access to
information and opportunity to correct or prevent such statement or omission.
The Underwriters' respective obligations to contribute pursuant to this Section
8 are several in proportion to their respective underwriting commitments, and
not joint.

         8.8. CONTRIBUTION AMOUNTS. The Sellers and the Underwriters agree that
it would not be just or equitable if contribution pursuant to this Section 8
were determined by PRO RATA allocation (even if the Underwriters were treated as
one entity for such purpose) or by any other method of allocation that does not
take account of the equitable considerations referred to in Section 8.7. The
amount paid or payable by an indemnified party as a result of the losses,
claims, damages and liabilities referred to in the immediately preceding
paragraph shall be deemed to include, subject to the limitations set forth
above, any legal or other expenses reasonably incurred by such indemnified party
in connection with investigating or defending any such action or claim.
Notwithstanding the provisions of this Section 8.8, no Underwriter shall be
required to contribute any amount in excess of the amount by which the total
price at which the Shares underwritten by it and distributed to the public were
offered to the public exceeds the amount of any damages that such Underwriter
has otherwise been required to pay by reason of such untrue or alleged untrue
statement or omission or alleged omission, and the Selling Stockholder shall not
be required to contribute any amount in excess of the net proceeds received by
such Selling Stockholder with respect to the Shares sold by such Selling
STOCKHOLDER. No person guilty of fraudulent misrepresentation (within the
meaning of Section 11(f) of the Securities Act) shall be entitled to
contribution from any person who was not guilty of such fraudulent
misrepresentation. The remedies provided for in this Section 8 are not exclusive
and shall not limit any rights or remedies which may otherwise be available to
any indemnified party at law or in equity; provided, however, the remedies as to
the Selling Stockholder shall be limited as set forth in the last sentence of
Section 8.3.

         9. SURVIVAL. The respective indemnity and contribution provisions,
agreements, representations, warranties and other statements of the Company, the
Selling Stockholder and the several Underwriters contained in this Agreement or
made by or on behalf of them respectively, pursuant to this Agreement shall
remain in full force and effect regardless of (i) any termination of this
Agreement, (ii) any investigation made by or on behalf of any Underwriter or any
person controlling any Underwriter, any Selling Stockholder or any person
controlling any Selling Stockholder, or the Company, its officers or directors
or any person controlling the Company and (iii) delivery of and payment for any
of the Shares.

         10. EFFECTIVENESS. This Agreement shall become effective upon the
execution and delivery hereof by the parties hereto.

         11. TERMINATION. This Agreement shall be subject to termination by
notice given by you to the Company, if (a) after the execution and delivery of
this Agreement and prior to the Closing Date (i) trading generally shall have
been suspended or materially limited on or by, as the case may be, any of the
New York Stock Exchange, the National Association of Securities Dealers, Inc.,
or the Nasdaq National Market ("Nasdaq"), (ii) trading of any securities of the
Company shall have been suspended by Nasdaq, (iii) a general moratorium on
commercial banking activities in New York, Delaware or California shall have
been declared by either federal or New York, Delaware or California state
authorities or (iv) there shall have occurred any outbreak or escalation of
hostilities or any change in financial markets or any calamity or crisis that,
in your reasonable judgment, is material and adverse, or (v) in the reasonable
judgment of the Representatives, there shall have occurred any material adverse
change, or any development that could


                                       18


reasonably be expected to result in a material adverse change, in the financial
condition or in the earnings, business or operations, whether or not arising
from transactions in the ordinary course of business, of the Company and its
subsidiaries, taken as a whole, and (b) in the case of any of the events
specified in clauses 11(a)(i) through 11(a)(v), such event, individually or
together with any other such event, makes it, in your reasonable judgment,
impracticable to market the Shares on the terms and in the manner contemplated
in the Prospectus.

         12. DEFAULTING UNDERWRITERS. If, on the Closing Date or the Option
Closing Date, as the case may be, any one or more of the Underwriters shall fail
or refuse to purchase Shares that it has or they have agreed to purchase
hereunder on such date, and the aggregate number of Shares which such defaulting
Underwriter or Underwriters agreed but failed or refused to purchase is not more
than one-tenth of the aggregate number of the Shares to be purchased on such
date, the other Underwriters shall be obligated severally in the proportions
that the number of Firm Shares set forth opposite their respective names in
SCHEDULE A bears to the aggregate number of Firm Shares set forth opposite the
names of all such non-defaulting Underwriters, or in such other proportions as
you may specify, to purchase the Shares which such defaulting Underwriter or
Underwriters agreed but failed or refused to purchase on such date; PROVIDED
that in no event shall the number of Shares that any Underwriter has agreed to
purchase pursuant to this Agreement be increased pursuant to this Section 12 by
an amount in excess of one-ninth of such number of Shares without the written
consent of such Underwriter. If, on the Closing Date, any Underwriter or
Underwriters shall fail or refuse to purchase Firm Shares and the aggregate
number of Firm Shares with respect to which such default occurs is more than
one-tenth of the aggregate number of Firm Shares to be purchased, and
arrangements satisfactory to you, the Company and the Selling Stockholder for
the purchase of such Firm Shares are not made within 36 hours after such
default, this Agreement shall terminate without liability on the part of any
non-defaulting Underwriter, the Company or the Selling Stockholder. In any such
case either you or the relevant Sellers shall have the right to postpone the
Closing Date, but in no event for longer than seven (7) days, in order that the
required changes, if any, in the Registration Statement and in the Prospectus or
in any other documents or arrangements may be effected. If, on the Option
Closing Date, any Underwriter or Underwriters shall fail or refuse to purchase
Additional Shares and the aggregate number of Additional Shares with respect to
which such default occurs is more than one-tenth of the aggregate number of
Additional Shares to be purchased, the non-defaulting Underwriters shall have
the option to (i) terminate their obligation hereunder to purchase Additional
Shares or (ii) purchase not less than the number of Additional Shares that such
non-defaulting Underwriters would have been obligated to purchase in the absence
of such default. Any action taken under this paragraph shall not relieve any
defaulting Underwriter from liability in respect of any default of such
Underwriter under this Agreement.

         If this Agreement shall be terminated by the Underwriters, or any of
them, because of any failure or refusal on the part of any Seller to comply with
the terms or to fulfill any of the conditions of this Agreement, or if for any
reason any Seller shall be unable to perform its obligations under this
Agreement, the Sellers will reimburse the Underwriters or such Underwriters as
have so terminated this Agreement with respect to themselves, severally, for all
out-of-pocket expenses (including the fees and disbursements of their counsel)
reasonably incurred by such Underwriters in connection with this Agreement or
the offering contemplated hereunder.

         13. COUNTERPARTS. This Agreement may be signed in counterparts, each of
which shall be an original, with the same effect as if the signatures thereto
and hereto were upon the same instrument.

         14. HEADINGS; TABLE OF CONTENTS. The headings of the sections of this
Agreement have been inserted for convenience of reference only and shall not be
deemed a part of this Agreement.


                                       19


         15. NOTICES. All communications hereunder shall be in writing and shall
be mailed, hand delivered or telecopied and confirmed to the parties hereto as
follows:

         If to the Representatives:

                  Thomas Weisel Partners LLC
                  One Montgomery Street, Suite 3700
                  San Francisco, California 94104
                  Facsimile:  (415) 364-2694
                  Attention:  E. James Streator III

         with a copy to:

                  Thomas Weisel Partners LLC
                  One Montgomery Street, Suite 3700
                  San Francisco, California 94104
                  Facsimile:  (415) 364-2694
                  Attention:  David A. Baylor, Esq.

                  and

                  Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.
                  One Financial Center
                  Boston, MA 02111
                  Facsimile (617) 542-2241
                  Attention: Stanford N. Goldman, Jr., Esq.

         If to the Company:

                  Harvard Bioscience, Inc.
                  84 October Hill Road
                  Holliston, MA 01746
                  Facsimile:  (508) 429-8478
                  Attention:  Chane Graziano, CEO

         with a copy to:

                  Goodwin, Procter & Hoar LLP
                  Exchange Place
                  Boston, MA 02109
                  Facsimile: (617) 523-1231
                  Attention:  H. David Henken, P.C.



                                       20


         If to the Selling Stockholder:

                  David Green
                  c/o Harvard Bioscience, Inc.
                  84 October Hill Road
                  Holliston, MA 01746
                  Facsimile:  (508) 429-8478

         with a copy to:

                  Goodwin, Procter & Hoar LLP
                  Exchange Place
                  Boston, MA 02109
                  Facsimile: (617) 523-1231
                  Attention:  H. David Henken, P.C.

Any party hereto may change the address for receipt of communications by giving
written notice to the others.

         16. SUCCESSORS. This Agreement will inure to the benefit of and be
binding upon the parties hereto, including any substitute Underwriters pursuant
to Section 12 hereof, and to the benefit of the officers and directors and
controlling persons referred to in Section 8, and in each case their respective
successors, and no other person will have any right or obligation hereunder. The
term "successors" shall not include any purchaser of the Shares as such from any
of the Underwriters merely by reason of such purchase.

         17. PARTIAL UNENFORCEABILITY. The invalidity or unenforceability of any
Section, paragraph or provision of this Agreement shall not affect the validity
or enforceability of any other Section, paragraph or provision hereof. If any
Section, paragraph or provision of this Agreement is for any reason determined
to be invalid or unenforceable, there shall be deemed to be made such minor
changes (and only such minor changes) as are necessary to make it valid and
enforceable.

         18. GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE OF NEW YORK APPLICABLE TO
AGREEMENTS MADE AND TO BE PERFORMED IN SUCH STATE.

         19. CONSENT TO JURISDICTION. Any legal suit, action or proceeding
arising out of or based upon this Agreement or the transactions contemplated
hereby ("RELATED PROCEEDINGS") may be instituted in the federal courts of the
United States of America located in the New York City or the courts of the State
of New York in each case located in the New York City (collectively, the
"SPECIFIED COURTS"), and each party irrevocably submits to the exclusive
jurisdiction (except for proceedings instituted in regard to the enforcement of
a judgment of any such court (a "RELATED JUDGMENT"), as to which such
jurisdiction is non-exclusive) of such courts in any such suit, action or
proceeding. Service of any process, summons, notice or document by mail to such
party's address set forth above shall be effective service of process for any
suit, action or other proceeding brought in any such court. The parties
irrevocably and unconditionally waive any objection to the laying of venue of
any suit, action or other proceeding in the Specified Courts and irrevocably and
unconditionally waive and agree not to plead or claim in any such court that any
such suit, action or other proceeding brought in any such court has been brought
in an inconvenient forum. Each party not located in the United States
irrevocably appoints CT Corporation System, which currently maintains an


                                       21


office in New York City, United States of America, as its agent to receive
service of process or other legal summons for purposes of any such suit, action
or proceeding that may be instituted in any state or federal court in New York
City.

         20. WAIVER OF IMMUNITY. With respect to any Related Proceeding, each
party irrevocably waives, to the fullest extent permitted by applicable law, all
immunity (whether on the basis of sovereignty or otherwise) from jurisdiction,
service of process, attachment (both before and after judgment) and execution to
which it might otherwise be entitled in the Specified Courts, and with respect
to any Related Judgment, each party waives any such immunity in the Specified
Courts or any other court of competent jurisdiction, and will not raise or claim
or cause to be pleaded any such immunity at or in respect of any such Related
Proceeding or Related Judgement, including, without limitation, any immunity
pursuant to the United States Foreign Sovereign Immunities Act of 1976, as
amended.

         21. FAILURE OF THE SELLING STOCKHOLDER TO SELL AND DELIVER SHARES. If
the Selling Stockholder shall fail to sell and deliver to the Underwriters the
Shares to be sold and delivered by such Selling Stockholder at the Closing Date
pursuant to this Agreement, then the Underwriters may at their option, by
written notice from the Representatives to the Company and the Selling
Stockholder, either (i) terminate this Agreement without any liability on the
part of any Underwriter or, except as provided in Sections 7 and 8 hereof, the
Company or the Selling Stockholder, or (ii) purchase the shares which the
Company and other Selling Stockholder have agreed to sell and deliver in
accordance with the terms hereof. If the Selling Stockholder shall fail to sell
and deliver to the Underwriters the Shares to be sold and delivered by such
Selling Stockholder pursuant to this Agreement at the Closing Date or the Option
Closing Date, then the Underwriters shall have the right, by written notice from
the Representatives to the Company and the Selling Stockholder, to postpone the
Closing Date or the Option Closing Date, as the case may be, but in no event for
longer than seven (7) days in order that the required changes, if any, to the
Registration Statement and the Prospectus or any other documents or arrangements
may be effected.

         22. ENTIRE AGREEMENT. This Agreement constitutes the entire agreement
of the parties to this Agreement and supersedes all prior written or oral and
all contemporaneous oral agreements, understandings and negotiations with
respect to the subject matter hereof.

         23. AMENDMENTS. This Agreement may only be amended or modified in
writing, signed by all of the parties hereto, and no condition herein (express
or implied) may be waived unless waived in writing by each party whom the
condition is meant to benefit.

         24. SOPHISTICATED PARTIES. Each of the parties hereto acknowledges that
it is a sophisticated business person who was adequately represented by counsel
during negotiations regarding the provisions hereof, including, without
limitation, the indemnification and contribution provisions of Section 8, and is
fully informed regarding said provisions. Each of the parties hereto further
acknowledges that the provisions of Section 8 hereto fairly allocate the risks
in light of the ability of the parties to investigate the Company, its affairs
and its business in order to assure that adequate disclosure has been made in
the Registration Statement, any preliminary prospectus and the Prospectus (and
any amendments and supplements thereto), as required by the Securities Act and
the Exchange Act.


                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]



                                       22


         If the foregoing is in accordance with your understanding of our
agreement, kindly sign and return to the Company the enclosed copies hereof,
whereupon this instrument, along with all counterparts hereof, shall become a
binding agreement in accordance with its terms.

                                   Very truly yours,

                                   HARVARD BIOSCIENCE, INC.


                                   By:
                                      ------------------------------
                                      Name:
                                      Title:


                                   The Selling Stockholder
                                   named in Schedule B hereto,
                                   acting severally



                                   By:
                                      ------------------------------
                                       Attorney-in-Fact


Accepted as of the date hereof

Thomas Weisel Partners LLC
Dain Rauscher Incorporated
ING Barings LLC

Acting severally on behalf
 of themselves and the
 several Underwriters named
 in Schedule A hereto.

By: Thomas Weisel Partners LLC



     By:
        ---------------------------
         Name:
         Title:




                                       23





                               SCHEDULE A


             UNDERWRITER            NUMBER OF FIRM        NUMBER OF ADDITIONAL
                                         SHARES                SHARES TO BE
                                    TO BE PURCHASED       PURCHASED IF MAXIMUM
                                                             OPTION EXERCISED

Thomas Weisel Partners LLC
Dain Rauscher Incorporated
ING Barings LLC
[NAMES OF OTHER UNDERWRITERS]











total











                                   SCHEDULE B


           SELLING                                        NUMBER OF FIRM
         STOCKHOLDER                                          SHARES
                                                            TO BE SOLD
DAVID GREEN













                                      Total







                                    EXHIBIT A

                    FORM OF LEGAL OPINION OF COMPANY COUNSEL


         THE FINAL OPINION IN DRAFT FORM SHOULD BE ATTACHED AS EXHIBIT A AT THE
TIME THIS AGREEMENT IS EXECUTED.

         1. The Company is a corporation duly incorporated, validly existing and
in good standing under the laws of the jurisdiction of its incorporation, has
the corporate power to conduct its business as described in the Prospectus and
is qualified to transact business as a foreign corporation and is in good
standing in each jurisdiction listed on Annex A to this opinion.

         2. Each subsidiary of the Company is a corporation validly existing and
in good standing under the laws of the jurisdiction of its incorporation, has
the corporate power to conduct its business as described in the Prospectus and
is qualified to transact business as a foreign corporation and is in good
standing in each jurisdiction listed next to its name on Annex B to this
opinion.

         3. All of the issued and outstanding shares of capital stock of the
Company have been duly authorized and validly issued and are fully paid and
non-assessable, free and clear of all liens, encumbrances, or claims. All of the
issued and outstanding shares of capital stock of each subsidiary of the Company
have been duly authorized and validly issued, are fully paid and non-assessable
and are owned of record by the Company or by a wholly-owned subsidiary of the
Company, free and clear of all liens, encumbrances, equities or claims, except
as disclosed in the Prospectus and any liens, encumbrances, equities or claims
generally placed on the Company's assets in the ordinary course of business.

         4. The authorized capital stock of the Company conforms, in all
material respects, as to legal matters to the description thereof contained in
the Prospectus.

         5. The shares of Common Stock (including the Shares to be sold by the
Selling Stockholder) outstanding prior to the issuance of the Shares to be sold
by the Company have been duly authorized and are validly issued, fully paid and
non-assessable.

         6. The Shares to be sold by the Company have been duly authorized and,
when issued and delivered in accordance with the terms of the Underwriting
Agreement, will be validly issued, fully paid and non-assessable, and the
issuance of such Shares will not be subject to any statutory preemptive or other
similar rights under the Company's certificate of incorporation, by-laws or, to
such counsel's knowledge, any agreement to which the Company is a party.

         7. The Underwriting Agreement has been duly authorized, executed and
delivered by the Company.

         8. The execution and delivery by the Company of, and the performance by
the Company of its obligations under, the Underwriting Agreement will not (i)
result in any violation of the provisions of the certificate of incorporation or
by-laws of the Company or, (ii) result in a breach or default on the part of the
Company under any agreement or other instrument filed as an exhibit to the
Registration Statement, or of which such counsel has knowledge, to which the
Company or any of its subsidiaries is a party or by which the Company or any of
its subsidiaries is bound, (iii) result in a violation on the part of the
Company of any




existing Massachusetts, Delaware General Corporation Law or federal statute or
regulation or, to such counsel's knowledge, any judgment, order or decree of any
body, agency or court and no consent, approval, authorization or order of, or
qualification with, any Massachusetts or federal body or agency is required to
be obtained by the Company for the performance by the Company of its obligations
under this Agreement, except that such counsel need express no opinion as to
state securities or "Blue Sky" laws or as to compliance with the antifraud
provisions of federal and state securities laws.

         9. The statements (A) in the Prospectus under the caption "Benefit
Plans," "Description of Capital Stock" and "Shares Eligible for Future Sale" and
(B) in the Registration Statement in Items 14 and 15, in each case insofar as
such statements constitute summaries of the legal matters, documents or
proceedings referred to therein, are accurate summaries in all material respects
of the matters referred to therein.

         10. To such counsel's knowledge, there are no legal or governmental
proceedings pending or threatened to which the Company or any of its
subsidiaries is a party or to which any of the properties of the Company or any
of its subsidiaries is subject that are required to be described in the
Registration Statement or the Prospectus and are not so described or of any
statutes, regulations, contracts or other documents that are required to be
described in the Registration Statement or the Prospectus or to be filed as
exhibits to the Registration Statement that are not described or filed as
required.

         11. The Company is not and, after giving effect to the offering and
sale of the Shares and the application of the proceeds thereof as described in
the Prospectus, will not be an "investment company" as such term is defined in
the Investment Company Act of 1940, as amended.

         Such counsel shall also state that as counsel to the Company, they have
reviewed the Registration Statement and the Prospectus, participated in
discussions with your representatives, those of counsel for the Underwriters,
and those of the Company and its accountants. On the basis of the information
that such counsel gained in the course of the performance of the services
referred to above, considered in the light of such counsel's understanding of
the applicable law and the experience such counsel has gained through its
practice under the Securities Act, such counsel will confirm to you that (i)
such counsel believes that the Registration Statement, as of its effective date,
and the Prospectus, as of the date of the Prospectus, appeared on their face to
be appropriately responsive in all material respects to the requirements of the
Securities Act and the applicable rules and regulations thereunder and (ii)
nothing that came to such counsel's attention in the course of such review has
caused such counsel to believe the Registration Statement, as of its effective
date, contained any untrue statement of a material fact or omitted to state any
material fact required to be stated therein or necessary to make the statements
therein not misleading, or that the Prospectus contained any untrue statement of
a material fact or omitted to state any material fact necessary in order to make
the statements therein, in light of the circumstances under which they were
made, not misleading.

         In addition, such counsel does not know of any litigation or any
governmental proceeding instituted or threatened against the Company or its
subsidiaries that would be required to be disclosed in the Prospectus that is
not so disclosed. Also, such counsel does not know of any documents that are
required to be filed as exhibits to the Registration Statement and are not so
filed or of any documents that are required to be summarized in the Registration
Statement and the Prospectus that are not so summarized.

         The limitations inherent in the independent verification of factual
matters and the character of determinations involved in the registration process
are such, however, that such counsel need not assume any responsibility for the
accuracy, completeness or fairness of the statements contained in the
Registration Statement except for those made under the captions "Benefit Plans,"
"Description of Capital Stock" and




"Shares Eligible for Future Sale" in the Prospectus, insofar as they accurately
summarize in all material respects the provisions of the laws and documents
referred to therein. Also, such counsel need not express any belief as to the
financial statements, other financial, statistical industry or operating data
and related schedules contained in the Registration Statement or the Prospectus.






                                    EXHIBIT B

             FORM OF LEGAL OPINION OF SELLING STOCKHOLDER'S COUNSEL


         THE FINAL OPINION IN DRAFT FORM SHOULD BE ATTACHED AS EXHIBIT B AT THE
TIME THIS AGREEMENT IS EXECUTED.

         1. The Underwriting Agreement has been duly executed and delivered by
or on behalf of the Selling Stockholder.

         2. The execution and delivery by the Selling Stockholder of, and the
performance by such Selling Stockholder of its obligations under, the
Underwriting Agreement and the Custody Agreement and Powers of Attorney of the
Selling Stockholder, will not (i) to such counsel's knowledge, result in a
breach or default on the part of the Selling Stockholder under any agreement or
other instrument as an exhibit to the Registration Statement to which such
Selling Stockholder is a party or by which the Selling Stockholder is bound or
(ii) result in a violation on the part of the Selling Stockholder of any
existing Massachusetts, Delaware General Corporation or federal statute or
regulation or, to such counsel's knowledge, any judgment, order or decree of any
body, agency or court, and no consent, approval, authorization or order of, or
qualification with, any Massachusetts or federal body or agency is required for
the performance by such Selling Stockholder of its obligations under the
Underwriting Agreement or the Custody Agreement or Power of Attorney of such
Selling Stockholder, except that such counsel need express no opinion as to
state securities or "Blue Sky" laws or as to compliance with the antifraud
provisisons of the federal and state securities laws.

         3. Upon delivery by the custodian to the Underwriters of the
certificates for the Shares to be sold by the Selling Stockholder pursuant to
the Underwriting Agreement duly endorsed for transfer, and upon payment therefor
in accordance with the terms of the Underwriting Agreement, the Underwriters who
have severally purchased such Shares pursuant to the Underwriting Agreement will
acquire all the rights in such Shares that the Selling Stockholder had or had
the power to transfer free of any adverse claim, assuming for the purposes of
this opinion that the Underwriters purchased the same without notice of any
adverse claim to such Shares.

         4. The Custody Agreement and the Power of Attorney of the Selling
Stockholder have been duly authorized, executed and delivered by such Selling
Stockholder and each such document constitutes a valid and binding obligation of
such Selling Stockholder.

         Such counsel may rely with respect to factual matters and to the extent
such counsel deems appropriate, upon the representations of the Selling
Stockholder contained in the Underwriting Agreement and in the Custody Agreement
and Power of Attorney of such Selling Stockholder and in other documents and
instruments; provided that copies of such Custody Agreement and Power of
Attorney and of any such other documents shall be delivered to counsel to the
Underwriters and shall be in form and substance satisfactory to counsel to the
Underwriters.








                                    EXHIBIT C

                    FORM OF PATENT OPINION OF COMPANY COUNSEL

         THE FINAL OPINION IN DRAFT FORM SHOULD BE ATTACHED AS EXHIBIT C at the
TIME THIS AGREEMENT IS EXECUTED.

         1. Based upon such counsel's (a) inquiry of the Company's
representatives responsible for patent matters and (b) such counsel's review of
the chain of title records that the Company's representative provided from the
United States Patent and Trademark Office ("USPTO") for the United States
patents and patent applications that the Company's representative provided, (i)
to such counsel's knowledge, the patent and pending patent applications that are
listed on Schedule A to the opinion ("Patents") have been validly assigned to
the Company or all inventors on such Patents are under an obligation to assign
all of their rights in such Patents to the Company, and (ii) except as provided
in Schedule A, the Company is listed as the sole holder of record of each of the
Patents. Except as provided in Schedule A, such counsel knows of no claim of a
third party to any ownership interest in, or to any lien with respect to, any of
the Patents. Except as provided in Schedule A, such counsel knows of no claim of
a third party to any ownership interest in, or to any lien with respect to, any
of the Patents, and knows of no nonjoined inventorship interest in any of the
Patents who is not under an obligation to assign his or her interest in the
invention to the Company. To such counsel's knowledge and based upon inquiry of
the Company's representatives responsible for patent matters, but without
inquiring into the dockets of any court, commission, administrative agency, or
other government body, no claim, action, or suit or proceeding is presently
pending or threatened against the Company relating to the potential infringement
of, or conflict with, any patents or others. Except as provided on Schedule A,
none of the Patents has been abandoned, lapsed, or been finally determined to be
unpatentable, invalid, unregisterable, or unenforceable by any court or
administrative tribunal having jurisdiction over any such matter.

         2. No fact has come to such counsel's attention that such counsel
believes is material to the examination of the patent applications that is not
of record or will not be made of record in the relevant application files of the
USPTO. No fact has come to such counsel's attention that causes such counsel to
believe that any Patent is unpatentable, unregisterable, invalid or
unenforceable.

         3. Without limiting the foregoing, we have not undertaken any
independent investigation to determine the existence or absence of such facts,
and no inference as to our knowledge of the existence or absence of such fact,
should be drawn from the fact of our representation of the Company in its patent
matters. To such counsel's knowledge and based upon inquiry of the Company's
representatives responsible for patent matters, but without inquiring into the
dockets of any court, commission, administrative agency, or other government
body, there are no threatened interference, opposition, public use,
reexamination, reissue, or protest proceedings with respect to any Patent.

         4. Based upon inquiry of the Company's representatives responsible for
patent matters, the patents and pending patent applications listed on Schedule B
to the opinion have been licensed to the Company.

         5. No facts have come to such counsel's attention which cause such
counsel to believe that the statements in the Prospectus relating to patent and
trademark matters under the caption "If we are unable to protect our proprietary
methods and technologies, we may not be able to operate our business profitably"
in "Risk Factors" and the caption "Intellectual Property" in "Business" result
in the Prospectus containing an untrue or misleading statement of material fact,
or omitting a material fact necessary to make the




statements therein not misleading. There can be no assurance that all material
facts were disclosed to us, or that our familiarity with the Company is such
that we have necessarily recognized the materiality of such facts as were
disclosed to us, and we have to a large extent relied upon statements of
representatives of the Company as to the materiality of the facts disclosed to
us.











                                    EXHIBIT D
                            FORM OF LOCK-UP AGREEMENT

                                                        _____________, 2000


Thomas Weisel Partners LLC
ING Barings LLC
As Representatives of the several Underwriters
c/o Thomas Weisel Partners LLC
One Montgomery Street, Suite 3700
San Francisco, California  94104

       Re:  LOCK-UP AGREEMENT (THE "AGREEMENT")

Ladies and Gentlemen:

         The undersigned is an owner of record or beneficially of certain shares
of Common Stock, par value $.01 per share (the "Common Stock"), of Harvard
Apparatus, Inc. or securities convertible into or exchangeable or exercisable
for Common Stock. In connection with the Public Offering (as defined below),
Harvard Apparatus, Inc. will be reincorporated by merger in Delaware as Harvard
Bioscience, Inc. References herein to the "Company" include Harvard Apparatus,
Inc., a Massachusetts corporation, and its successor, Harvard Bioscience, Inc.,
a Delaware corporation, as applicable. The undersigned understands that you, as
representatives (the "Representatives"), propose to enter into an Underwriting
Agreement on behalf of the several Underwriters named in SCHEDULE A to such
agreement (collectively, the "Underwriters"), with the Company providing for a
public offering of the Common Stock of the Company pursuant to a Registration
Statement on form S-1 to be filed with the Securities and Exchange Commission
(the "Public Offering"). The undersigned recognizes that the Public Offering
will be of benefit to the undersigned and will benefit the Company by, among
other things, raising additional capital for its operations. The undersigned
acknowledges that you and the other Underwriters are relying on the
representations and agreements of the undersigned contained in this letter in
carrying out the Public Offering and in entering into underwriting arrangements
with the Company with respect to the Public Offering.

         To induce the Underwriters that may participate in the Public Offering
to continue their efforts in connection with the Public Offering, the
undersigned hereby agrees that, without the prior written consent of Thomas
Weisel Partners (which consent may be withheld in its sole discretion), it will
not, during the period commencing on the date hereof and ending 180 days after
the date of the final prospectus relating to the Public Offering (the
"Prospectus"), (1) offer, pledge, sell, contract to sell, sell any option or
contract to purchase, purchase any option or contract to sell, grant any option,
right or warrant to purchase, lend, or otherwise transfer or dispose of,
directly or indirectly, any shares of Common Stock or any securities convertible
into or exercisable or exchangeable for Common Stock, or (2) enter into any swap
or other arrangement that transfers to another, in whole or in part, any of the
economic consequences of ownership of the Common Stock, whether any such
transaction described in clause (1) or (2) above is to be settled by delivery of
Common Stock or such other securities, in cash or otherwise. In addition, the
undersigned agrees that, without the prior written consent of Thomas Weisel
Partners (which consent may be withheld in its sole discretion), it will not,
during the period commencing on the date hereof and ending 180 days after the
date of the Prospectus, make any demand for or exercise any right with respect
to, the registration of any shares of Common Stock or any security convertible
into or exercisable or exchangeable for Common Stock. With respect to the Public
Offering, the undersigned waives any registration rights relating to
registration under the




Securities Act of any Common Stock owned either of record or beneficially by the
undersigned, including, without limitation, any rights to receive notice of the
Public Offering and any rights under that certain Amended and Restated
Securityholders' Agreement dated as of March 2, 1999 by and among the Company,
Ascent Venture Partners, L.P. (as assignee of Pioneer Ventures Limited
Partnership and Pioneer Capital Corp.), Ascent Venture Partners II, L.P.
(formerly known as Pioneer Ventures Limited Partnership II), First New England
Capital, L.P., Citizens Capital, Inc., Chane Graziano and David Green.

         The foregoing restrictions are expressly agreed to preclude the
undersigned from engaging in any hedging or other transaction which is designed
to or reasonably expected to lead to or result in a sale or disposition of the
Common Stock even if such Common Stock would be disposed of by someone other
than the undersigned. Such prohibited hedging or other transactions would
include without limitation any short sale or any purchase, sale or grant of any
right (including without limitation any put option or put equivalent position or
call option or call equivalent position) with respect to any of the Common Stock
or with respect to any security that includes, relates to, or derives any
significant part of its value from such Common Stock.

         Notwithstanding the foregoing, the undersigned may transfer shares of
Common Stock (i) as a BONA FIDE gift or gifts, provided that the donee or donees
thereof agree to be bound by the restrictions set forth herein, (ii) to any
trust for the direct or indirect benefit of the undersigned or the immediate
family of the undersigned, provided that the trustee of the trust agrees to be
bound by the restrictions set forth herein, and provided further that any such
transfer shall not involve a disposition for value, (iii) to the Underwriters
pursuant to the Underwriting Agreement, or (iv) in transactions relating to
shares of Common Stock acquired by the undersigned in open market transactions
after the completion of the Public Offering. For purposes of this Agreement,
"immediate family" shall mean any relationship by blood, marriage or adoption,
not more remote than first cousin. In addition, notwithstanding the foregoing,
if the undersigned is a corporation, the corporation may transfer the capital
stock of the Company to any wholly-owned subsidiary of such corporation;
PROVIDED, HOWEVER, that in any such case, it shall be a condition to the
transfer that the transferee execute an agreement stating that the transferee is
receiving and holding such capital stock subject to the provisions of this
Agreement and there shall be no further transfer of such capital stock except in
accordance with this Agreement, and provided further that any such transfer
shall not involve a disposition for value. In addition, notwithstanding anything
contained herein to the contrary, at any time prior to the date on which the
Registration Statement on Form S-1 filed with the Securities and Exchange
Commission relating to the Public Offering is declared effective by the
Securities and Exchange Commission, the undersigned may transfer shares of
Common Stock; PROVIDED, HOWEVER, that in any such case, it shall be a condition
to the transfer that (i) the transferee execute and deliver a lock-up agreement,
in the form of the lock-up agreement executed by the transferor, and (ii) the
transferor provide notice of such transfer to the Representatives of the
Underwriters.

         The undersigned understands that whether or not the Public Offering
actually occurs depends on a number of factors, including stock market
conditions. The Public Offering will only be made pursuant to an Underwriting
Agreement, the terms of which are subject to negotiation among the Company and
the Underwriters. Notwithstanding anything contained herein to the contrary, if
the Public Offering is terminated or suspended by either the Underwriters or the
Company, this lock-up agreement shall be of no further force or effect.

         The undersigned agrees and consents to the entry of stop transfer
instructions with the Company's transfer agent and registrar against the
transfer of shares of Common Stock or securities convertible into or
exchangeable or exercisable for Common Stock held by the undersigned except in
compliance with the foregoing restrictions.




         This agreement is irrevocable and will be binding on the undersigned
and the respective successors, heirs, personal representatives, and assigns of
the undersigned.



                                             Very truly yours,


                                             -----------------------------
                                             (Name)

                                             -----------------------------
                                             (Address)