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                                                                     EXHIBIT 4.1

                         AMERICAN PACIFIC CORPORATION

                            2001 STOCK OPTION PLAN

     1.  Purpose of the Plan.

         This 2001 Stock Option Plan (the "Plan") is intended as an incentive,
to retain key employees, directors, consultants and advisors to AMERICAN PACIFIC
CORPORATION, a Delaware corporation (the "Company"), and any Subsidiary of the
Company within the meaning of Section 424(f) of the United States Internal
Revenue Code of 1986, as amended (the "Code"), having experience and ability, to
attract new employees, directors, consultants and advisors whose services are
considered valuable, to encourage the sense of proprietorship and to stimulate
the active interest of such persons in the development and financial success of
the Company and its Subsidiaries.

         It is further intended that certain options granted pursuant to the
Plan shall constitute incentive stock options within the meaning of Section 422
of the Code (the "Incentive Options") while certain other options granted
pursuant to the Plan shall be nonqualified stock options (the "Nonqualified
Options"). Incentive Options and Nonqualified Options are hereinafter referred
to collectively as "Options."

         The Company intends that the Plan meet the requirements of Rule 16b-3
("Rule 16b-3") promulgated under the Securities Exchange Act of 1934, as amended
(the "Exchange Act") and that transactions of the type specified in
subparagraphs (c) to (f) inclusive of Rule 16b-3 by officers and directors of
the Company pursuant to the Plan be exempt from the operation of Section 16(b)
of the Exchange Act. Further, the Plan is intended to satisfy the
performance-based compensation exception to the limitation on the Company's tax
deductions imposed by Section 162(m) of the Code. In all cases, the terms,
provisions, conditions and limitations of the Plan shall be construed and
interpreted consistent with the Company's intent as stated in this Section 1.

     2.  Administration of the Plan.

         The Board of Directors of the Company (the "Board") shall appoint and
maintain as administrator of the Plan a Committee (the "Committee") consisting
of two or more directors who are "Non-Employee Directors" (as such term is
defined in Rule 16b-3) and "Outside Directors" (as such term is defined in
Section 162(m) of the Code), which shall serve at the pleasure of the Board. The
Committee, subject to Sections 3 and 5 hereof, shall have full power and
authority to designate recipients of Options, to determine the terms and
conditions of respective Option agreements (which need not be identical) and to
interpret the provisions and supervise the administration of the Plan. The
Committee shall have the authority, without limitation, to designate which
Options granted under the Plan shall be Incentive Options and which shall be
Nonqualified Options. To the extent any Option does not qualify as an Incentive
Option, it shall constitute a separate Nonqualified Option.

         Subject to the provisions of the Plan, the Committee shall interpret
the Plan and all Options granted under the Plan, shall make such rules as it
deems necessary for the proper administration of the Plan, shall make all other
determinations necessary or advisable for the administration of the Plan and
shall correct any defects or supply any omission or reconcile any inconsistency
in the Plan or in any Options granted under the Plan in the manner and to the
extent that the Committee deems desirable to carry into effect the Plan or any
Options. The act or determination of a majority of the Committee shall be the
act or determination of the Committee and any decision reduced to writing and
signed by all of the members of the Committee shall be fully effective as if it
had been made by a majority at a meeting duly held. Subject to the provisions of
the Plan, any action taken or determination made by the Committee pursuant to
this and the other Sections of the Plan shall be conclusive on all parties.

         In the event that for any reason the Committee is unable to act or if
the Committee at the time of any grant, award or other acquisition under the
Plan of Options or Stock as hereinafter defined does not consist of two or more
Non-Employee Directors, or if there shall be no such Committee, then the Plan
shall be administered by the Board, and references herein to the Committee
(except in the proviso to this sentence) shall be deemed to be references to the
Board, and any such grant, award or other acquisition may be approved or
ratified in any other manner contemplated by subparagraph (d) of Rule 16b-3;
provided, however, that options granted to the Company's Chief Executive Officer
--------  -------
or to any of the Company's other four most highly compensated officers that are
intended to
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qualify as performance-based compensation under Section 162(m) of the Code may
only be granted by the Committee.

     3.  Designation of Optionees.

         The persons eligible for participation in the Plan as recipients of
Options (the "Optionees") shall include employees, officers and directors of,
and consultants and advisors to, the Company or any Subsidiary; provided that
Incentive Options may only be granted to employees of the Company and the
Subsidiaries. In selecting Optionees, and in determining the number of shares to
be covered by each Option granted to Optionees, the Committee may consider the
office or position held by the Optionee or the Optionee's relationship to the
Company, the Optionee's degree of responsibility for and contribution to the
growth and success of the Company or any Subsidiary, the Optionee's length of
service, age, promotions, potential and any other factors that the Committee may
consider relevant. An Optionee who has been granted an Option hereunder may be
granted an additional Option or Options, if the Committee shall so determine.

     4.  Stock Reserved for the Plan.

         Subject to adjustment as provided in Section 7 hereof, a total of
350,000 shares of the Company's Common Stock, $0.10 par value per share (the
"Stock"), shall be subject to the Plan. The maximum number of shares of Stock
that may be subject to options granted under the Plan to any individual in any
calendar year shall not exceed 50,000, and the method of counting such shares
shall conform to any requirements applicable to performance-based compensation
under Section 162(m) of the Code. The shares of Stock subject to the Plan shall
consist of unissued shares or previously issued shares held by any Subsidiary of
the Company, and such amount of shares of Stock shall be and is hereby reserved
for such purpose. Any of such shares of Stock that may remain unsold and that
are not subject to outstanding Options at the termination of the Plan shall
cease to be reserved for the purposes of the Plan, but until termination of the
Plan the Company shall at all times reserve a sufficient number of shares of
Stock to meet the requirements of the Plan. Should any Option expire or be
canceled prior to its exercise in full or should the number of shares of Stock
to be delivered upon the exercise in full of an Option be reduced for any
reason, the shares of Stock theretofore subject to such Option may be subject to
future Options under the Plan, except where such reissuance is inconsistent with
the provisions of Section 162(m) of the Code.

     5.  Terms and Conditions of Options.

         Options granted under the Plan shall be subject to the following
conditions and shall contain such additional terms and conditions, not
inconsistent with the terms of the Plan, as the Committee shall deem desirable:

         (a) Option Price. The purchase price of each share of Stock purchasable
             ------------
under any Option shall be determined by the Committee at the time of grant, but
shall not be less than 100% of the Fair Market Value (as defined below) of such
share of Stock on the date the Option is granted; provided, however, that with
                                                  --------  -------
respect to an Incentive Option granted to an Optionee who, at the time such
Incentive Option is granted, owns (within the meaning of Section 424(d) of the
Code) more than 10% of the total combined voting power of all classes of stock
of the Company or of any Subsidiary, the purchase price per share of Stock shall
be at least 110% of the Fair Market Value per share of Stock on the date of
grant. The exercise price for each Option shall be subject to adjustment as
provided in Section 7 below. "Fair Market Value" means the closing price of
publicly traded shares of Stock on the principal securities exchange on which
shares of Stock are listed (if the shares of Stock are so listed), or on the
NASDAQ Stock Market (if the shares of Stock are regularly quoted on the NASDAQ
Stock Market), or, if not so listed or regularly quoted, the mean between the
closing bid and asked prices of publicly traded shares of Stock in the
over-the-counter market, or, if such bid and asked prices shall not be
available, as reported by any nationally recognized quotation service selected
by the Company, or as determined by the Committee in a manner consistent with
the provisions of the Code. Anything in this Section 5(a) to the contrary
notwithstanding, in no event shall the purchase price of a share of Stock be
less than the minimum price permitted under the rules and policies of any
national securities exchange on which the shares of Stock are listed.

         (b) Option Term. The term of each Option shall be fixed by the
             -----------
Committee, but no Option shall be exercisable more than ten years after the date
such Option is granted and in the case of an Incentive Option granted to an
Optionee who, at the time such Incentive Option is granted, owns (within the
meaning of Section

                              Exhibit 4.1 Page 2
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424(d) of the Code) more than 10% of the total combined voting power of all
classes of stock of the Company or of any Subsidiary, no such Incentive Option
shall be exercisable more than five years after the date such Incentive Option
is granted.

         (c) Exercisability. Subject to Section 5(j) hereof, Options shall be
             --------------
exercisable at such time or times and subject to such terms and conditions as
shall be determined by the Committee at the time of grant.

             Upon the occurrence of a "Change in Control" (as hereinafter
defined), the Committee may accelerate the vesting and exercisability of
outstanding Options, in whole or in part, as determined by the Committee in its
sole discretion. In its sole discretion, the Committee may also determine that,
upon the occurrence of a Change in Control, each outstanding Option shall
terminate within a specified number of days after notice to the Optionee
thereunder, and each such Optionee shall receive, with respect to each share of
Company Stock subject to such Option, an amount equal to the excess of the Fair
Market Value of such shares immediately prior to such Change in Control over the
exercise price per share of such Option; such amount shall be payable in cash,
in one or more kinds of property (including the property, if any, payable in the
transaction) or a combination thereof, as the Committee shall determine in its
sole discretion.

             For purposes of the Plan, a Change in Control shall be deemed to
have occurred if:

             (i)    a tender offer (or series of related offers) shall be made
         and consummated for the ownership of 30% or more of the outstanding
         voting securities of the Company, unless as a result of such tender
         offer more than 50% of the outstanding voting securities of the
         surviving or resulting corporation shall nevertheless be owned in the
         aggregate by the shareholders of the Company (as of the time
         immediately prior to the commencement of such offer), any employee
         benefit plan of the Company or its Subsidiaries, and their affiliates;

              (ii)  the Company shall be merged or consolidated with another
         corporation, unless as a result of such merger or consolidation more
         than 50% of the outstanding voting securities of the surviving or
         resulting corporation shall be owned in the aggregate by the
         shareholders of the Company (as of the time immediately prior to such
         transaction), any employee benefit plan of the Company or its
         Subsidiaries, and their affiliates;

              (iii) the Company shall sell substantially all of its assets to
         another corporation that is not wholly owned by the Company, unless as
         a result of such sale more than 50% of such assets shall be owned in
         the aggregate by the shareholders of the Company (as of the time
         immediately prior to such transaction), any employee benefit plan of
         the Company or its Subsidiaries and their affiliates; or

              (iv)  a Person (as defined below) shall acquire 50% or more of the
         outstanding voting securities of the Company (whether directly,
         indirectly, beneficially or of record), unless as a result of such
         acquisition more than 50% of the outstanding voting securities of the
         surviving or resulting corporation shall be owned in the aggregate by
         the shareholders of the Company (as of the time immediately prior to
         the first acquisition of such securities by such Person), any employee
         benefit plan of the Company or its Subsidiaries, and their affiliates.

              For purposes of this Section 5(c), ownership of voting securities
shall take into account and shall include ownership as determined by applying
the provisions of Rule 13d-3(d)(I)(i) (as in effect on the date hereof) under
the Exchange Act. In addition, for such purposes, "Person" shall have the
meaning given in Section 3(a)(9) of the Exchange Act, as modified and used in
Sections 13(d) and 14(d) thereof; however, a Person shall not include (A) the
Company or any of its Subsidiaries; (B) a trustee or other fiduciary holding
securities under an employee benefit plan of the Company or any of its
Subsidiaries; (C) an underwriter temporarily holding securities pursuant to an
offering of such securities; or (D) a corporation owned, directly or indirectly,
by the shareholders of the Company in substantially the same proportion as their
ownership of stock of the Company.

         (d)  Method of Exercise. Options to the extent then exercisable may be
              ------------------
exercised in whole or in part at any time during the option period, by giving
written notice to the Company specifying the number of

                              Exhibit 4.1 Page 3
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shares of Stock to be purchased, accompanied by payment in full of the purchase
price, in cash, or by check or such other instrument as may be acceptable to the
Committee. As determined by the Committee, in its sole discretion, at or after
grant, payment in full or in part may be made at the election of the Optionee
(i) in the form of Stock owned by the Optionee (based on the Fair Market Value
of the Stock on the trading day before the Option is exercised) that is not the
subject of any pledge or security interest, (ii) in the form of shares of Stock
withheld by the Company from the shares of Stock otherwise to be received with
such withheld shares of Stock having a Fair Market Value on the date of exercise
equal to the exercise price of the Option, or (iii) by a combination of the
foregoing, provided that the combined value of all cash and cash equivalents and
the Fair Market Value of any shares surrendered to the Company is at least equal
to such exercise price and except with respect to (ii) above, such method of
payment will not cause a disqualifying disposition of all or a portion of the
Stock received upon exercise of an Incentive Option. An Optionee shall have the
right to dividends and other rights of a stockholder with respect to shares of
Stock purchased upon exercise of an Option at such time as the Optionee has
given written notice of exercise and has paid in full for such shares and (ii)
has satisfied such conditions that may be imposed by the Company with respect to
the withholding of taxes.

         (e) Non-transferability of Options. Options are not transferable and
             ------------------------------
may be exercised solely by the Optionee during his lifetime or after his death
by the person or persons entitled thereto under his will or the laws of descent
and distribution. The Committee, in its sole discretion, may permit a transfer
of a Nonqualified Option to (i) a trust for the benefit of the Optionee or (ii)
a member of the Optionee's immediate family (or a trust for his or her benefit).
Any attempt to transfer, assign, pledge or otherwise dispose of, or to subject
to execution, attachment or similar process, any Option contrary to the
provisions hereof shall be void and ineffective and shall give no right to the
purported transferee.

         (f) Termination by Death. Unless otherwise determined by the Committee
             --------------------
at grant, if any Optionee's employment with or service to the Company or any
Subsidiary terminates by reason of death, the Option may thereafter be
exercised, to the extent then exercisable (or on such accelerated basis as the
Committee shall determine at or after grant), by the legal representative of the
estate or by the legatee of the Optionee under the will of the Optionee, for a
period of one year after the date of such death or until the expiration of the
stated term of such Option as provided under the Plan, whichever period is
shorter.

         (g) Termination by Reason of Disability. Unless otherwise determined by
             -----------------------------------
the Committee at grant, if any Optionee's employment with or service to the
Company or any Subsidiary terminates by reason of total and permanent
disability, any Option held by such Optionee may thereafter be exercised, to the
extent it was exercisable at the time of termination due to Disability (or on
such accelerated basis as the Committee shall determine at or after grant), but
may not be exercised after one year after the date of such termination of
employment or service or the expiration of the stated term of such Option,
whichever period is shorter; provided, however, that, if the Optionee dies
within such one year period, any unexercised Option held by such Optionee shall
thereafter be exercisable to the extent to which it was exercisable at the time
of death for a period of one year after the date of such death or for the stated
term of such Option, whichever period is shorter.

         (h) Termination by Reason of Retirement. Unless otherwise determined by
             -----------------------------------
the Committee at grant, if any Optionee's employment with or service to the
Company or any Subsidiary terminates by reason of Normal or Early Retirement (as
such terms are defined below), any Option held by such Optionee may thereafter
be exercised to the extent it was exercisable at the time of such Retirement (or
on such accelerated basis as the Committee shall determine at or after grant),
but may not be exercised after three months after the date of such termination
of employment or service or the expiration of the stated term of such Option,
whichever period is shorter; provided, however, that, if the Optionee dies
within such three month period, any unexercised Option held by such Optionee
shall thereafter be exercisable, to the extent to which it was exercisable at
the time of death, for a period of one year after the date of such death or for
the stated term of such Option, whichever period is shorter.

         For purposes of this paragraph (h) "Normal Retirement" shall mean
retirement from active employment with the Company or any Subsidiary on or after
the normal retirement date specified in the applicable Company or Subsidiary
pension plan or if no such pension plan, age 65, and "Early Retirement" shall
mean retirement from active employment with the Company or any Subsidiary
pursuant to the early retirement provisions of the applicable Company or
Subsidiary pension plan or if no such pension plan, age 55.

                              Exhibit 4.1 Page 4
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         (i) Other Termination. Unless otherwise determined by the Committee at
             -----------------
grant, if any Optionee's employment with or service to the Company or any
Subsidiary terminates for any reason other than death, Disability or Normal or
Early Retirement, the Option shall thereupon terminate, except that the portion
of any Option that was exercisable on the date of such termination of employment
or service may be exercised for the lesser of three months after the date of
termination or the balance of such Option's term if the Optionee's employment or
service with the Company or any Subsidiary is terminated by the Company or such
Subsidiary without cause (the determination as to whether termination was for
cause to be made by the Committee). The transfer of an Optionee from the employ
of or service to the Company to the employ of or service to a Subsidiary, or
vice versa, or from one Subsidiary to another, shall not be deemed to constitute
a termination of employment or service for purposes of the Plan.

         (j) Limit on Value of Incentive Option. The aggregate Fair Market
             ----------------------------------
Value, determined as of the date the Incentive Option is granted, of Stock for
which Incentive Options are exercisable for the first time by any Optionee
during any calendar year under the Plan (and/or any other stock option plans of
the Company or any Subsidiary) shall not exceed $100,000.

         (k) Transfer of Incentive Option Shares. The stock option agreement
             ------------------------------------
evidencing any Incentive Options granted under this Plan shall provide that if
the Optionee makes a disposition, within the meaning of Section 424(c) of the
Code and regulations promulgated thereunder, of any share or shares of Stock
issued to him upon exercise of an Incentive Option granted under the Plan within
the two-year period commencing on the day after the date of the grant of such
Incentive Option or within a one-year period commencing on the day after the
date of transfer of the share or shares to him pursuant to the exercise of such
Incentive Option, he shall, within 10 days after such disposition, notify the
Company thereof and immediately deliver to the Company any amount of United
States federal, state and local income tax withholding required by law.

     6.  Term of Plan.

         No Option shall be granted pursuant to the Plan on or after January 16,
2011, but Options theretofore granted may extend beyond that date.

     7.  Capital Change of the Company.

         In the event of any merger, reorganization, consolidation,
recapitalization, stock dividend, or other change in corporate structure
affecting the Stock, the Committee shall make an appropriate and equitable
adjustment in the number and kind of shares reserved for issuance under the Plan
and in the number and option price of shares subject to outstanding Options
granted under the Plan, to the end that after such event each Optionee's
proportionate interest shall be maintained as immediately before the occurrence
of such event.

     8.  Purchase for Investment.

         Unless the Options and shares covered by the Plan have been registered
under the Securities Act of 1933, as amended (the "Securities Act"), or the
Company has determined that such registration is unnecessary, each person
exercising an Option under the Plan may be required by the Company to give a
representation in writing that he is acquiring the shares for his own account
for investment and not with a view to, or for sale in connection with, the
distribution of any part thereof.

     9.  Taxes.

         The Company may make such provisions as it may deem appropriate,
consistent with applicable law, in connection with any Options granted under the
Plan with respect to the withholding of any taxes or any other tax matters.

     10. Effective Date of Plan.

         The Plan shall be effective on January 16, 2001, provided the Plan is
subsequently approved by majority vote of the Company's stockholders not later
than January 15, 2002.

                              Exhibit 4.1 Page 5
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         11.      Amendment and Termination.

                  The Board may amend, suspend, or terminate the Plan, except
that no amendment shall be made that would impair the rights of any Optionee
under any Option theretofore granted without the Optionee's consent, and except
that no amendment shall be made which, without the approval of the stockholders
of the Company would:

                  (a)      increase the number of shares that may be issued
under the Plan, except as is provided in Section 7;

                  (b)      materially increase the benefits accruing to the
Optionees under the Plan;

                  (c)      materially modify the requirements as to eligibility
for participation in the Plan;

                  (d)      decrease the exercise price of an Option to less than
100% of the Fair Market Value per share of Stock on the date of grant thereof;
or

                  (e)      extend the term of any Option beyond that provided
for in Section 5(b).

                  The Committee may amend the terms of any Option theretofore
granted, prospectively or retroactively, but no such amendment shall impair the
rights of any Optionee without the Optionee's consent. The Committee may also
substitute new Options for previously granted Options, including options granted
under other plans applicable to the participant and previously granted Options
having higher option prices, upon such terms as the Committee may deem
appropriate.

         12.      Government Regulations.

                  The Plan, and the grant and exercise of Options hereunder, and
the obligation of the Company to sell and deliver shares under such Options,
shall be subject to all applicable laws, rules and regulations, and to such
approvals by any governmental agencies, national securities exchanges and
interdealer quotation systems as may be required.

         13.      General Provisions.

                  (a)      Certificates. All certificates for shares of Stock
                           ------------
delivered under the Plan shall be subject to such stop transfer orders and other
restrictions as the Committee may deem advisable under the rules, regulations
and other requirements of the Securities and Exchange Commission, or other
securities commission having jurisdiction, any applicable Federal or state
securities law, any stock exchange or interdealer quotation system upon which
the Stock is then listed or traded and the Committee may cause a legend or
legends to be placed on any such certificates to make appropriate reference to
such restrictions.

                  (b)      Employment Matters. The adoption of the Plan shall
                           ------------------
not confer upon any Optionee of the Company or any Subsidiary any right to
continued employment or, in the case of an Optionee who is a director, continued
service as a director, with the Company or a Subsidiary, as the case may be, nor
shall it interfere in any way with the right of the Company or any Subsidiary to
terminate the employment of any of its employees, the service of any of its
directors or the retention of any of its consultants or advisors at any time.

                  (c)      Limitation of Liability. No member of the Board or
                           -----------------------
the Committee, or any officer or employee of the Company acting on behalf of the
Board or the Committee, shall be personally liable for any action, determination
or interpretation taken or made in good faith with respect to the Plan, and all
members of the Board or the Committee and each and any officer or employee of
the Company acting on their behalf shall, to the fullest extent permitted by
law, be fully indemnified and protected by the Company in respect of any such
action, determination or interpretation.

                              Exhibit 4.1 Page 6
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                  (d)      Registration of Stock. Notwithstanding any other
                           ---------------------
provision in the Plan, no Option may be exercised unless and until the Stock to
be issued upon the exercise thereof has been registered under the Securities Act
and applicable state securities laws, or is, in the opinion of counsel to the
Company, exempt from such registration in the United States. The Company shall
not be under any obligation to register under applicable federal or state
securities laws any Stock to be issued upon the exercise of an Option granted
hereunder in order to permit the exercise of an Option and the issuance and sale
of the Stock subject to such Option, although the Company may in its sole
discretion register such Stock at such time as the Company shall determine. If
the Company chooses to comply with such an exemption from registration, the
Stock issued under the Plan may, at the direction of the Committee, bear an
appropriate restrictive legend restricting the transfer or pledge of the Stock
represented thereby, and the Committee may also give appropriate stop transfer
instructions with respect to such Stock to the Company's transfer agent.

         14.      Governing Law.

                  The law of the State of Delaware shall govern all questions
concerning the construction, validity and interpretation of this Plan, without
regard to such state's conflict of laws rules.


                         AMERICAN PACIFIC CORPORATION
                               January 16, 2001



                              Exhibit 4.1 Page 7