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                                                                    EXHIBIT 10.1

                                   N2H2, INC.
                             2000 STOCK OPTION PLAN

        ARTICLE 1. INTRODUCTION.

        The purpose of the Plan is to promote the long-term success of the
Company and the creation of shareholder value by encouraging the attraction and
retention of Employees and Consultants with exceptional qualifications and
linking Employees and Consultants directly to shareholder interests through
increased stock ownership.

        The Plan shall be governed by, and construed in accordance with, the
laws of the State of Washington.

        ARTICLE 2. ADMINISTRATION.

        2.1 Committee Composition. The Plan shall be administered by the
Committee. The Committee shall consist exclusively of two or more directors of
the Company, who shall be appointed by the Board. In addition, the composition
of the Committee shall satisfy:

        (a) Such requirements as the Securities and Exchange Commission may
establish for administrators acting under plans intended to qualify for
exemption under Rule 16b-3 (or its successor) under the Exchange Act; and

        (b) Such requirements as the Internal Revenue Service may establish for
outside directors acting under plans intended to qualify for exemption under
Section 162(m)(4)(C) of the Code.

        2.2 Committee Responsibilities. The Committee shall (a) select the
Employees and Consultants who are to receive Options under the Plan, (b)
determine the type, number, vesting requirements and other features and
conditions of Options, (c) interpret the Plan and (d) make all other decisions
relating to the operation of the Plan. The Committee may adopt such rules or
guidelines as it deems appropriate to implement the Plan. The Committee's
determinations under the Plan shall be final and binding on all persons.

        2.3 Committee for Non-Officer Grants. The Board may also appoint a
secondary committee of the Board, which shall be composed of two or more
directors of the Company who need not satisfy the requirements of Section 2.1.
Such secondary committee may administer the Plan with respect to Employees and
Consultants who are not considered executive officers or directors of the
Company under Section 16 of the Exchange Act, may grant Options under the Plan
to such Employees and Consultants and may determine all features and conditions
of such Options. Within the limitations of this Section 2.3, any reference in
the Plan to the Committee shall include such secondary committee.

        ARTICLE 3. SHARES AVAILABLE FOR GRANTS.

        3.1 Basic Limitation. Common Shares issued pursuant to the Plan shall be
authorized but unissued shares. The aggregate number of Common Shares issued
pursuant to Options awarded under the Plan shall not exceed (a) 4,000,000 plus
(b) the additional Common Shares described in Section 3.2. The limitation of
this Section 3.1 shall be subject to adjustment pursuant to Article 7.

        3.2 Additional Shares. If Options are forfeited or terminate for any
other reason before being exercised, then the corresponding Common Shares shall
again become available for the grant of Options under the Plan.

        ARTICLE 4.    ELIGIBILITY.

        4.1 Nonstatutory Stock Options. Only Employees and Consultants shall be
eligible for the grant of NSOs.

        4.2 Incentive Stock Options. Only Employees who are common-law employees
of the Company, a Parent or a Subsidiary shall be eligible for the grant of
ISOs.


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In addition, an Employee who owns more than 10% of the total combined voting
power of all classes of outstanding stock of the Company or any of its Parents
or Subsidiaries shall not be eligible for the grant of an ISO unless the
requirements set forth in Section 422(c)(6) of the Code are satisfied.

        ARTICLE 5. OPTIONS.

        5.1 Stock Option Agreement. Each grant of an Option under the Plan shall
be evidenced by a Stock Option Agreement between the Optionee and the Company.
Such Option shall be subject to all applicable terms of the Plan and may be
subject to any other terms that are not inconsistent with the Plan. The
provisions of the various Stock Option Agreements entered into under the Plan
need not be identical.

        5.2 Number of Shares. Each Stock Option Agreement shall specify the
number of Common Shares subject to the Option and shall provide for the
adjustment of such number in accordance with Article 7. Options granted to any
Optionee in a single fiscal year of the Company shall not cover more than
100,000 Common Shares, except that Options granted to a new Employee in the
fiscal year of the Company in which his or her service as an Employee first
commences shall not cover more than 200,000 Common Shares. The limitations set
forth in the preceding sentence shall be subject to adjustment in accordance
with Article 7.

        5.3 Exercise Price. Each Stock Option Agreement shall specify the
Exercise Price; provided that the Exercise Price under an ISO shall in no event
be less than 100% of the Fair Market Value of a Common Share on the date of
grant.

        5.4 Exercisability and Term. Each Stock Option Agreement shall specify
the date or event when all or any installment of the Option is to become
exercisable. The Stock Option Agreement shall also specify the term of the
Option; provided that the term of an ISO shall in no event exceed 10 years from
the date of grant. A Stock Option Agreement may provide for accelerated
exercisability in the event of the Optionee's death, disability or retirement or
other events and may provide for expiration prior to the end of its term in the
event of the termination of the Optionee's service.

        5.5 Effect of Change in Control. The Committee may determine, at the
time of granting an Option or thereafter, that such Option shall become
exercisable as to all or part of the Common Shares subject to such Option in the
event that a Change in Control occurs with respect to the Company provided that
in the case of an ISO, the acceleration of exercisability shall not occur
without the Optionee's written consent.

        5.6 Modification of Options. Within the limitations of the Plan, the
Committee may modify outstanding options. The foregoing notwithstanding, no
modification of an Option shall, without the consent of the Optionee, alter or
impair his or her rights or obligations under such Option.

        5.7 Buyout Provisions. The Committee may at any time (a) offer to buy
out for a payment in cash or cash equivalents an Option previously granted or
(b) authorize an Optionee to elect to cash out an Option previously granted, in
either case at such time and based upon such terms and conditions as the
Committee shall establish.

        ARTICLE 6. PAYMENT FOR OPTION SHARES.

        6.1 General Rule. The entire Exercise Price of Common Shares issued upon
exercise of Options shall be payable in cash or cash equivalents at the time
when such Common Shares are purchased, except as follows:

        (a) In the case of an ISO granted under the Plan, payment shall be made
only pursuant to the express provisions of the applicable Stock Option
Agreement. The Stock Option Agreement may specify that payment may be made in
any form(s) described in this Article 6.

        (b) In the case of an NSO, the Committee may at any time accept payment
in any form(s) described in this Article 6.


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        6.2 Surrender of Stock. To the extent that this Section 6.2 is
applicable, all or any part of the Exercise Price may be paid by surrendering,
or attesting to the ownership of, Common Shares that are already owned by the
Optionee. Such Common Shares shall be valued at their Fair Market Value on the
date when the new Common Shares are purchased under the Plan. The Optionee shall
not surrender, or attest to the ownership of, Common Shares in payment of the
Exercise Price if such action would cause the Company to recognize compensation
expense (or additional compensation expense) with respect to the Option for
financial reporting purposes.

        6.3 Exercise/Sale. To the extent that this Section 6.3 is applicable,
all or any part of the Exercise Price and any withholding taxes may be paid by
delivering (on a form prescribed by the Company) an irrevocable direction to a
securities broker approved by the Company to sell all or part of the Common
Shares being purchased under the Plan and to deliver all or part of the sales
proceeds to the Company.

        6.4 Exercise/Pledge. To the extent that this Section 6.4 is applicable,
all or any part of the Exercise Price and any withholding taxes may be paid by
delivering (on a form prescribed by the Company) an irrevocable direction to
pledge all or part of the Common Shares being purchased under the Plan to a
securities broker or lender approved by the Company, as security for a loan, and
to deliver all or part of the loan proceeds to the Company.

        6.5 Other Forms of Payment. To the extent that this Section 6.5 is
applicable, all or any part of the Exercise Price and any withholding taxes may
be paid in any other form that is consistent with applicable laws, regulations
and rules.

        ARTICLE 7 PROTECTION AGAINST DILUTION.

        7.1 Adjustments. In the event of a subdivision of the outstanding Common
Shares, a declaration of a dividend payable in Common Shares, a declaration of a
dividend payable in a form other than Common Shares in an amount that has a
material effect on the price of Common Shares, a combination or consolidation of
the outstanding Common Shares (by reclassification or otherwise) into a lesser
number of Common Shares, a recapitalization, a spin-off or a similar occurrence,
the Committee shall make such adjustments as it, in its sole discretion, deems
appropriate in one or more of:

        (a) The number of Options available for future grants under Article 3;

        (b) The limitations set forth in Section 5.2;

        (c) The number of Common Shares covered by each outstanding Option; or

        (d) The Exercise Price under each outstanding Option.

Except as provided in this Article 7, an Optionee shall have no rights by reason
of any issue by the Company of stock of any class or securities convertible into
stock of any class, any subdivision or consolidation of shares of stock of any
class, the payment of any stock dividend or any other increase or decrease in
the number of shares of stock of any class.

        7.2 Dissolution or Liquidation. To the extent not previously exercised,
Options shall terminate immediately prior to the dissolution or liquidation of
the Company.

        7.3 Reorganizations. In the event that the Company is a party to a
merger or other reorganization, outstanding Options shall be subject to the
agreement of merger or reorganization. Such agreement shall provide for:

        (a) The continuation of the outstanding Options by the Company, if the
Company is a surviving corporation;

        (b) The assumption of the outstanding Options by the surviving
corporation or its parent or subsidiary;


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        (c) The substitution by the surviving corporation or its parent or
subsidiary of its own options for the outstanding Options;

        (d) Full exercisability or vesting and accelerated expiration of the
outstanding Options; or

        (e) Settlement of the full value of the outstanding Options in cash or
cash equivalents followed by cancellation of such Options.

        ARTICLE 8. LIMITATION ON RIGHTS.

        8.1 Retention Rights. Neither the Plan nor any Option granted under the
Plan shall be deemed to give any individual a right to remain an Employee or
Consultant. The Company and its Parents, Subsidiaries and Affiliates reserve the
right to terminate the service of any Employee or Consultant at any time, with
or without cause, subject to applicable laws, the Company's Articles of
Incorporation and Bylaws and a written employment agreement (if any).

        8.2 Shareholders' Rights. A Participant shall have no dividend rights,
voting rights or other rights as a shareholder with respect to any Common Shares
covered by his or her Option prior to the time when he or she becomes entitled
to receive such Common Shares by filing a notice of exercise and paying the
Exercise Price. No adjustment shall be made for cash dividends or other rights
for which the record date is prior to such time, except as expressly provided in
the Plan.

        8.3 Regulatory Requirements. Any other provision of the Plan
notwithstanding, the obligation of the Company to issue Common Shares under the
Plan shall be subject to all applicable laws, rules and regulations and such
approval by any regulatory body as may be required. The Company reserves the
right to restrict, in whole or in part, the delivery of Common Shares pursuant
to any Option prior to the satisfaction of all legal requirements relating to
the issuance of such Common Shares, to their registration, qualification or
listing or to an exemption from registration, qualification or listing.

        ARTICLE 9. WITHHOLDING TAXES.

        9.1 General. To the extent required by applicable federal, state, local
or foreign law, an Optionee or his or her successor shall make arrangements
satisfactory to the Company for the satisfaction of any withholding tax
obligations that arise in connection with the Plan. The Company shall not be
required to issue any Common Shares or make any cash payment under the Plan
until such obligations are satisfied.

        9.2 Share Withholding. The Committee may permit an Optionee to satisfy
all or part of his or her withholding or income tax obligations by having the
Company withhold all or a portion of any Common Shares that otherwise would be
issued to him or her or by surrendering all or a portion of any Common Shares
that he or she previously acquired. Such Common Shares shall be valued at their
Fair Market Value on the date when taxes otherwise would be withheld in cash.

        ARTICLE 10. FUTURE OF THE PLAN.

        10.1 Term of the Plan. The Plan, as set forth herein, shall become
effective upon approval by the Company's shareholders. The Plan shall remain in
effect until it is terminated under Section 10.2, except that no ISOs shall be
granted on or after the 10th anniversary of the later of (a) the date when the
Board adopted the Plan or (b) the date when the Board adopted the most recent
increase in the number of Common Shares available under Article 3 which was
approved by the Company's shareholders.

        10.2 Amendment or Termination. The Board may, at any time and for any
reason, amend or terminate the Plan. An amendment of the Plan shall be subject
to the approval of the Company's shareholders to the extent required by
applicable laws, regulations or rules. The termination of the Plan, or any
amendment thereof, shall not affect any Option previously granted under the
Plan.


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        ARTICLE 11. DEFINITIONS.

        11.1 "Affiliate" means any entity other than a Subsidiary, if the
Company and/or one or more Subsidiaries own not less than 50% of such entity.

        11.2 "Board" means the Company's Board of Directors, as constituted from
time to time.

        11.3 "Change in Control" shall mean:

        (a) The execution of an agreement by the Company or the shareholder of
the Company providing for the merger or consolidation of the Company with or
into another entity or any other corporate reorganization, if more than 50% of
the combined voting power of the continuing or surviving entity's securities
outstanding immediately after such merger, consolidation or other reorganization
is owned by persons who were not shareholders of the Company immediately prior
to such merger, consolidation or other reorganization;

        (b) The execution of an agreement by the Company or the shareholder of
the Company providing for the sale, transfer or other disposition of all or
substantially all of the Company's assets;

        (c) A change in the composition of the Board, as a result of which fewer
than 50% of the incumbent directors are directors who either (i) had been
directors of the Company on the date 24 months prior to the date of the event
that may constitute a Change in Control (the "original directors") or (ii) were
elected, or nominated for election, to the Board with the affirmative votes of
at least a majority of the aggregate of the original directors who were still in
office at the time of the election or nomination and the directors whose
election or nomination was previously so approved; or

        (d) Any transaction as a result of which any person is the "beneficial
owner" (as defined in Rule 13d-3 under the Exchange Act), directly or
indirectly, of securities of the Company representing at least 40% of the total
voting power represented by the Company's then outstanding voting securities.
For purposes of this Subsection (d), the term "person" shall have the same
meaning as when used in Sections 13(d) and 14(d) of the Exchange Act but shall
exclude (i) a trustee or other fiduciary holding securities under an employee
benefit plan of the Company or of a Parent or Subsidiary and (ii) a corporation
owned directly or indirectly by the shareholders of the Company in substantially
the same proportions as their ownership of the common stock of the Company.

A transaction shall not constitute a Change in Control if its sole purpose is to
change the state of the Company's incorporation or to create a holding company
that will be owned in substantially the same proportions by the persons who held
the Company's securities immediately before such transaction.

        11.4 "Code" means the Internal Revenue Code of 1986, as amended.

        11.5 "Committee" means a committee of the Board, as described in
Article 2.

        11.6 "Common Share" means one share of the common stock of the Company,
no par value per share.

        11.7 "Company" means N2H2, Inc., a Washington corporation.

        11.8 "Consultant" means a consultant or adviser who provides bona fide
services to the Company, a Parent, a Subsidiary or an Affiliate as an
independent contractor. Service as a Consultant shall be considered employment
for all purposes of the Plan, except as provided in Section 4.2.

        11.9 "Employee" means a common-law employee of the Company, a Parent, a
Subsidiary or an Affiliate.

        11.10 "Exchange Act" means the Securities Exchange Act of 1934, as
amended.


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        11.11 "Exercise Price" means the amount for which one Common Share may
be purchased upon exercise of such Option, as specified in the applicable Stock
Option Agreement.

        11.12 "Fair Market Value" means the market price of Common Shares,
determined by the Committee in good faith on such basis as it deems appropriate.
Whenever possible, the determination of Fair Market Value by the Committee shall
be based on the prices reported in the Wall Street Journal. Such determination
shall be conclusive and binding on all persons.

        11.13 "ISO" means an incentive stock option described in Section 422(b)
of the Code.

        11.14 "NSO" means a stock option not described in Sections 422 or 423 of
the Code.

        11.15 "Option" means an ISO or NSO granted under the Plan and entitling
the holder to purchase Common Shares.

        11.16  "Optionee" means an individual or estate who holds an Option.

        11.17 "Parent" means any corporation (other than the Company) in an
unbroken chain of corporations ending with the Company, if each of the
corporations other than the Company owns stock possessing 50% or more of the
total combined voting power of all classes of stock in one of the other
corporations in such chain. A corporation that attains the status of a Parent on
a date after the adoption of the Plan shall be considered a Parent commencing as
of such date.

        11.18 "Plan" means this N2H2, Inc. 2000 Stock Option Plan, as amended
from time to time.

        11.19 "Stock Option Agreement" means the agreement between the Company
and an Optionee that contains the terms, conditions and restrictions pertaining
to his or her Option.

        11.20 "Subsidiary" means any corporation (other than the Company) in an
unbroken chain of corporations beginning with the Company, if each of the
corporations other than the last corporation in the unbroken chain owns stock
possessing 50% or more of the total combined voting power of all classes of
stock in one of the other corporations in such chain. A corporation that attains
the status of a Subsidiary on a date after the adoption of the Plan shall be
considered a Subsidiary commencing as of such date.