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                                                                   EXHIBIT 10.21

                 ASSIGNMENT, RESEARCH AND DEVELOPMENT AGREEMENT

     THIS AGREEMENT is entered into as of the 30th day of August, 2000 (the
"Effective Date") by and among IPG Photonics Corporation, a Delaware corporation
("Photonics"), IPG Laser GmbH, a German corporation ("Laser") and IPG Fibertech
S.R.L., an Italian corporation ("Fibertech") (collectively, the "Developers")
and NTO "IRE-POLUS", a Russian Corporation ("Contractor") (each, a "Party" and
collectively, the "Parties").

                                    RECITALS

     WHEREAS, the Developers desire to engage Contractor to assist in the
development of the Developed Technology and Intellectual Property;

     WHEREAS, Contractor has the expertise and facilities to undertake such
development work, and is willing to undertake such work.

     NOW, THEREFORE, in consideration of the premises and of the mutual promises
hereinafter set forth, the Parties hereto agree as follows:

                                    ARTICLE 1
                                   DEFINITIONS

     For purposes of this Agreement, the following definitions shall apply to
the terms set forth herein:

     1.1 Contracts. "Contracts" shall mean those contracts listed on Exhibit E
attached hereto between Contractor and Laser pursuant to which Laser purchased
certain products or goods and/or research and development services or other
services and an irrevocable, exclusive, royalty-free, unconditional, worldwide
right to use all intellectual property rights relating to such products and
services. Such Contracts constitute all of the agreements and understandings
between Contractor and Laser for the development of Intellectual Property.

     1.2 Developed Technology. "Developed Technology" shall mean the property
listed in Exhibit A to this Agreement.

     1.3 Development Costs. "Development Costs" shall mean the Contractor's
direct and indirect costs as set forth in Exhibit C to this Agreement.

     1.4 Development Plan. "Development Plan" shall mean the written strategy
for development of a Project, including, without limitation, the nature and
timing of research, and other appropriate matters, which shall be agreed on by
Developers and Contractor.

     1.5 Improvements. "Improvements" shall mean any findings, discoveries,
inventions, derivative works, additions, modifications, formulations, or changes
made by either Developers or Contractor during the term of this Agreement that
relate to the Developed Technology, Intellectual Property or any Product.

     1.6 Intellectual Property. "Intellectual Property" shall mean the property
listed in Exhibit A to this Agreement.

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     1.7 Product. "Product" shall mean the property listed in Exhibit A to this
Agreement.

     1.8 Project or Projects. "Project" or "Projects" shall mean the research
project(s) listed from time-to-time in Exhibit D to this
Agreement.

     1.9 Related Party. "Related Party" shall mean any legal entity directly or
indirectly controlled by, controlling, or under common control
with the Developers.

     1.10 Third Party or Third Parties. "Third Party" or "Third Parties" shall
mean any entity other than a party to this Agreement.

     1.11 Year. "Year" shall mean the twelve-month period ending on December 31
or such other annual accounting period as may be adopted by the Parties.

                                    ARTICLE 2
                            PROJECTS AND COMPENSATION

     2.1 Initiation. Contractor shall promptly undertake each Project once the
Development Plan for such Project has been agreed upon by the Developers and
Contractor.

     2.2 Reports. Contractor shall provide monthly reports to the Developers on
the progress that has been made with respect to the Project(s) (the "Report").
Each Report shall be submitted no later than fifteen (15) days following the end
of each month and shall have such form and substance as shall be specified by
Developers.

     2.3 Payment by Developers. Each Report shall identify the Development Costs
that have been incurred by Contractor with respect to each Project during the
period covered by such Report, including a corporate overhead fee equal to ten
(10) percent of such costs. Developers shall pay Contractor the amount of such
costs within thirty (30) days following receipt by Developers of each Report.

     2.4 Access to Project. Developers shall have the right at their expense to
have their employees or agents inspect during normal business hours the
facilities wherein the Project(s) is being conducted, including, without
limitation, books and records relating to the Development Costs and the research
materials that are compiled by the professional staff of Contractor.

     2.5 Exclusivity. The Contractor shall not perform services involving the
development of Intellectual Property for any person, firm or corporation other
than the Developers.

                                    ARTICLE 3
                   GRANT OF RIGHT TO USE INTELLECTUAL PROPERTY

     3.1 Grant by Developer. Developers grant to Contractor the limited
nonexclusive right to use, develop, and enjoy the Intellectual Property solely
for the purpose of completing the Project(s), subject to the terms and
conditions of this Agreement. Such limited license and right shall terminate
automatically upon termination of a Development Plan or this Agreement.


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     3.2 No Further Transfer. Contractor shall not assign, sublicense, make
available, or otherwise transfer or disclose any right to use, develop, or
otherwise enjoy the Intellectual Property without the express written consent of
Developer.

     3.3 Limited Uses by Contractor. Notwithstanding anything to the contrary
herein, Contractor shall have the limited, non-exclusive right to use the
Technology (as defined below), Developed Technology, Intellectual Property and
Improvements in connection with the Contractor's manufacture, marketing, sale
and use of (a) Products in the countries that comprised the former Union of
Soviet Socialist Republics for use in those countries, and (b) unless
unanimously agreed to by Photonics' Board of Directors, other products and
services (i) not involving telecommunications; (ii) not related to projects
undertaken for Developer currently and in the future; and (iii) not related to
the Developer's current and future business.

                                    ARTICLE 4
                   EXCHANGE OF INFORMATION AND CONFIDENTIALITY

     4.1 Intellectual Property. During the term of this Agreement, Developers
shall disclose to Contractor such of their Intellectual Property as Contractor
reasonably needs to complete the Project.

     4.2 Improvements. During the term of this Agreement, each Party shall
promptly inform the other party of any information that it obtains or develops
regarding Improvements.

     4.3 Confidentiality. During the Term of this Agreement, and for a period
often (10) years from the date of expiration or termination of this Agreement,
Contractor shall treat this Agreement, Intellectual Property, Developed
Technology, Products, Improvements, and all information, data, reports, and
other records that it receives from Developers as secret, confidential, and
proprietary ("Confidential Information"), and shall not disclose or use such
Information without the prior written consent of the Developers except as
provided in this Agreement. Contractor shall develop and implement such
procedures as may be required to prevent the intentional or negligent disclosure
to Third Parties of Confidential Information communicated to Contractor and its
employees and agents by Developers, including, but not limited to, requiring
each of its employees and agents having access to such information under this
Agreement to enter into an appropriate nondisclosure agreement with Contractor
for the benefit of the Developers.

     4.4 Nothing in this Agreement shall prevent the disclosure by Contractor or
its employees and agents of Confidential Information that:

          (a)  Prior to the transmittal thereof to Contractor was of general
               public knowledge;

          (b)  Becomes, subsequent to the time of transmittal to Contractor, a
               matter of general public knowledge otherwise than as a
               consequence of a breach by Contractor of any obligation under
               this Agreement;

          (c)  Is made public by Developers;

          (d)  Was in the possession of Contractor in documentary form prior


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               to the time of disclosure thereof to Contractor by Developers,
               and is held by Contractor free of any obligation of confidence to
               Developers or any Third Party; or

          (e)  Is received in good faith from a Third Party having the right to
               disclose it, who, to the best of Contractors knowledge, did not
               obtain such information from Developers and who imposes no
               obligation of secrecy on Contractor with respect to such
               information.

                                    ARTICLE 5
                                    OWNERSHIP

     5.1 Intellectual Property Ownership. Contractor acknowledges Developers'
exclusive right, title, and interest in and to the Developed Technology;
Improvements and Intellectual Property. Contractor shall not itself, nor shall
it permit its employees and agents, to at any time do or cause to be done, or
fail to do or cause to be done, any act or thing, directly or indirectly,
contesting or in any way impairing Developer's right, title, or interest in the
Developed Technology, Improvements and Intellectual Property. Every use of any
Developed Technology, Improvements and Intellectual Property by Contractor shall
inure to the benefit of Developers.

     5.2 Ownership of Rights. Photonics, on behalf of Developers shall at all
times, during or after the term of this Agreement, be the sole owner of all
rights relating to or emanating from Intellectual Property, Developed
Technology, Improvements, or other matters developed in, or related to, a
Project. All such works shall belong exclusively to Photonics, with Photonics
having the right to obtain and to hold in its own name, copyright registrations,
patents and such other intellectual property protection as may be appropriate to
the subject matter, and any extensions and renewals thereof. All works of
Contractor, its employees and agents, subject to or protectable under copyright
laws of any country shall, to the fullest extent possible, be works made for
hire. To the extent such works do not qualify as works made for hire, Contractor
hereby sells, assigns and transfers to Photonics and shall sell, assign and
transfer to Photonics, on behalf of Developers, all of its right, title and
interest in such works including all moral rights where permitted by law and all
rights of renewal and the right to sue and recover for infringement or
misappropriation or unfair competition related to such works. Contractor agrees
to give Photonics, and any person designated by Photonics, reasonable
assistance, at Photonics' expense, required to perfect the rights defined in
this Section, including, but not limited to, executing and delivering all
documents requested by Photonics in connection therewith. Unless otherwise
directed by Photonics, upon the completion of the Services or upon the earlier
termination of the engagement, Contractor shall immediately turn over to
Photonics all such works as well as all materials and deliverables developed,
including, but not limited to, working papers, descriptions, reports, notes and
data. All such works shall bear Photonics' copyright and trade secret notices,
as specified by Photonics. No rights to such works shall remain with Contractor.

                                   ARTICLE 5A
                                   ASSIGNMENT

     5A.1 For good and valuable consideration, the receipt and sufficiency of
which is hereby acknowledged, the Contractor hereby confirms, acknowledges and
agrees with Laser that it hereby conveys and assigns to Laser, its


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successors and assigns, the entire right, title and interest, including any and
all intellectual property rights therein or relating thereto, in and to the (a)
any and all goods, products or services described in each Contract and (b) the
technology, processes and know how relating to such goods, products or services
(collectively, the "Technology").

     5A.2 Neither Contractor nor any of its officers, directors, employees or
affiliates, will at any time reveal to any person or entity any of the trade
secrets or confidential information relating to the goods, products, or services
described in each Contract or the Technology without the prior written consent
of Laser, and shall not use or attempt to use any such information in any manner
which may injure or cause loss or may be calculated to cause loss whether
directly or indirectly to Laser.

                                    ARTICLE 6
                              TERM AND TERMINATION

     6.1 Term. This Agreement shall remain in effect, unless sooner terminated
by mutual consent of the Parties, until the termination of the last Project
agreed on by the Parties.

     6.2 Termination. Either Developers or Contractor shall have the right to
terminate this Agreement at any time, by giving written notice to the Party in
default on the occurrence of any of the following events:

          (a)  A Party fails or neglects to perform covenants or provisions of
               this Agreement if such default is not corrected within sixty (60)
               days after receiving written notice from the other Party with
               respect to such default;

          (b)  Any act, determination, filing, judgment, declaration, notice,
               appointment of receiver or trustee, failure to pay debts, or
               other events under any law applicable to a Party indicating the
               insolvency or bankruptcy of such Party;

          (c)  The taking of any extraordinary governmental action, including,
               without limitation, seizure or nationalization of assets, stock,
               or other property relating to a Party; or

          (d)  Any other event that shall cause Developers to have concern about
               the solvency, stability and/or freedom of Contractor from
               governmental seizure or interference.

     6.3 Termination by Developer. A Developer may terminate this Agreement at
any lime by providing thirty (30) days prior written notice to Contractor of
such termination.

     6.4 Rights and Duties on Termination. On termination of this Agreement,
Contractor shall return to Developers all Intellectual Property, Improvements,
and any and all Confidential Information disclosed to it by Developers in its
possession and all such items, and all Improvements shall be the exclusive
property of Developers.

     6.5 Survival. Termination of this Agreement by either Party pursuant to the
provisions of this Article 6 shall terminate each Party's obligations under this
Agreement except for the provisions of Articles 4, 5, SA, 7 and Section 8.10,
all of which shall survive the termination of this Agreement.


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                                    ARTICLE 7
                                 INDEMNIFICATION

     Contractor shall hold Developers harmless and shall indemnify Developers
from and against any loss, cost, or expense, including reasonable attorneys'
fees, related to any act or omission in connection with the performance or
nonperformance of its duties under the terms of this Agreement or any breach of
any representation and warranty made by Contractor in this Agreement.

                                    ARTICLE 8
                            MISCELLANEOUS PROVISIONS

     8.1 Notices. Any and all notices, elections, offers, acceptances, and
demands permitted or required to be made under this Agreement shall be in
writing, signed by the Party giving such notice, election, offer, acceptance, or
demand and shall be delivered personally, or sent by registered or certified
mail, to the Party, at its address on file with the other party or at such other
address as may be supplied in writing. The date of personal delivery or the date
of mailing, as the case may be, shall be the date of such notice, election,
offer, acceptance, or demand.

     8.2 Force Majeure. If the performance of any part of this Agreement by any
Party, or of any obligation under this Agreement, is prevented, restricted,
interfered with or delayed by reason of any cause beyond the reasonable control
of the Party liable to perform, unless conclusive evidence to the contrary is
provided, the Party so affected shall, on giving written notice to the other
party, be excused from such performance to the extent of such prevention,
restriction, interference or delay, provided that the affected Party shall use
its reasonable best efforts to avoid or remove such causes of nonperformance and
shall continue performance with the utmost dispatch whenever such causes are
removed. When such circumstances arise, the Parties shall discuss what, if any,
modification of the terms of this Agreement may be required in order to arrive
at an equitable solution.

     8.3 Successors and Assigns. This Agreement shall be binding on and shall
inure to the benefit of the Parties and any Related Party, their respective
successors and assigns, and each Party agrees, to execute any instruments that
may be necessary or appropriate to carry out and execute the purpose and
intentions of this Agreement and hereby authorizes and directs its successors
and assigns to execute any and all such instruments. Each and every successor in
interest to any Party, whether such successor acquires such interest by way of
gift, devise, assignment, purchase, conveyance, pledge, hypothecation,
foreclosure, or by any other method, shall hold such interest subject to all of
the terms and provisions of this Agreement. The rights of the Parties, and their
successors in interest, as among themselves and shall be governed by the terms
of this Agreement, and the right of any Party, or successor in interest to
assign, sell, or otherwise transfer or deal with its interests under this
Agreement shall be subject to the limitations and restrictions of this
Agreement.

     8.4 Amendment. No change, modification, or amendment of this Agreement
shall be valid or binding on the Parties unless such change or modification
shall be in writing signed by the Party or Parties against whom the same is
sought to be enforced.

     8.5 Remedies Cumulative. The remedies of the Parties under this Agreement
are cumulative and shall not exclude any other remedies to which


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the Party may be lawfully entitled.

     8.6 Further Assurances. Each Party hereby covenants and agrees that it
shall execute and deliver such deeds and other documents as may be required to
implement any of the provisions of this Agreement.

     8.7 Specific Performance. The Parties acknowledge that they will be damaged
if this Agreement is not specifically enforced. Therefore, in the event of a
breach by any party of any provision of this Agreement, the other parties shall
be entitled, in addition to all other rights or remedies available to them, to
injunctions restraining such breach, without being required to post any bond or
other security, and/or to a decree for specific performance of the provisions of
this Agreement.

     8.8 No Waiver. The failure of any Party to insist on strict performance of
a covenant hereunder or of any obligation hereunder shall not be a waiver of
such Party's right to demand strict compliance therewith in the future, nor
shall the same be construed as a breach of this Agreement.

     8.9 Integration. This Agreement constitutes the full and complete agreement
of the Parties with respect to the subject matter hereof.

     8.10 Counterparts. This Agreement may be executed in multiple copies, each
of which shall for all purposes constitute one and the same agreement, binding
on the Parties, and each Party hereby covenants and agrees to execute all
duplicates or replacement counterparts of this Agreement as may be required.

     8.11 Governing Law/Jurisdiction. This Agreement shall be construed and
enforced in accordance with and governed by the laws of the State of New York
(without giving effect to principles of conflicts of law). All actions and
proceedings arising out of or relative to this Agreement shall be heard and
determined in a Massachusetts state or federal court sitting in the City of
Boston. The parties hereby irrevocably submit to the exclusive jurisdiction of
any Massachusetts state or federal court sitting in the City of Boston in any
action or proceeding arising out of or relating to this Agreement, and hereby
irrevocably agree that all claims in respect of such action or proceeding may be
heard and determined in such Massachusetts state or federal court. The parties
hereby irrevocably waive, to the fullest extent they may effectively do so, the
defense of an inconvenient forum to the maintenance of such action or
proceeding. The parties agree that a final judgment in any such action or
proceeding shall be conclusive and may be enforced in other jurisdictions by
suit on the judgment or in any other manner provided by law. TO THE EXTENT NOT
PROHIBITED BY APPLICABLE LAW THAT CANNOT BE WAIVED, EACH PARTY HEREBY WAIVES,
AND COVENANTS THAT IT WILL NOT ASSERT (WHETHER AS PLAINTIFF, DEFENDANT OR
OTHERWISE), ANY RIGHT TO TRIAL BY JURY IN ANY FORUM IN RESPECT OF ANY ISSUE,
CLAIM, DEMAND, ACTION OR CAUSE OF ACTION ARISING OUT OF OR PASSED UPON THIS
AGREEMENT OR THE SUBJECT MATTER HEREOF, WHETHER NOW EXISTING OR HEREAFTER
ARISING AND WHETHER SOUNDING IN TORT OR CONTRACT OR OTHERWISE. This Agreement
will not be governed by the United Nations Convention of Contracts for the
International Sale of Goods, the application of which is hereby expressly
excluded.

     8.12 Severability. In the event any provision, clause, sentence, phrase, or
word hereof, or the application thereof in any circumstances, is held to be
invalid or unenforceable, such invalidity or unenforceability shall not affect
the validity or enforceability of the remainder hereof, or of the


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application of any such provision, sentence, clause, phrase, or word in any
other circumstances.

                            [Signature Pages Follow]


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The Parties, intending to be legally bound, have signed this Agreement as of the
Effective Date.

                                        IPG PHOTONICS CORPORATION


                                        By: /s/ Peter Veghese Mammen
                                            ------------------------------------
                                        Printed Name: Peter Verghese Mammen
                                        Title: Treasurer
                                        Date: 8/30/00


                                        IPG LASER GMBH


                                        By /s/ Dr. Valentin Gapontsev
                                           -------------------------------------
                                        Printed Name: Dr Valentin Gapontsev
                                        Title: Gerschaftsfuhrer
                                        Date: 8/30/00

       [Signature Page to Assignment, Research and Development Agreement)


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                                        IPG FIBERTECH S.R.L.


                                        By: /s/ Dr. Valentin Gapontsev
                                            ------------------------------------
                                        Printed Name: Dr Valentin Gaponstev
                                        Title: Director
                                        Date: 8/30/00


                                        NTO-IRE Polus


                                        By: /s/ Dr. Valentin Gapontsev
                                            ------------------------------------
                                        Printed Name: Dr Valentin Gaponstev
                                        Title: General Director
                                        Date: 8/30/00

       [Signature Page to Assignment, Research and Development Agreement]


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