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                                                                     EXHIBIT 4.2

                               BMC SOFTWARE, INC.

                             2000 STOCK OPTION PLAN


                             I. PURPOSE OF THE PLAN

         The BMC SOFTWARE, INC. 2000 STOCK OPTION PLAN (the "Plan") is intended
to provide a means whereby certain employees and consultants of BMC SOFTWARE,
INC., a Delaware corporation (the "Company"), and its affiliates may develop a
sense of proprietorship and personal involvement in the development and
financial success of the Company, and to encourage them to remain with and
devote their best efforts to the business of the Company, thereby advancing the
interests of the Company and its shareholders. A further purpose of the Plan is
to permit the Company to provide incentives to individuals who serve as
employees and consultants to entities that are acquired by the Company or one of
its affiliates. Accordingly, the Company may grant to certain employees and
consultants ("Optionees") the option ("Option") to purchase shares of the common
stock of the Company ("Stock"), as hereinafter set forth. Options granted under
the Plan shall not be treated as incentive stock options, within the meaning of
section 422(b) of the Internal Revenue Code of 1986, as amended (the "Code").

                               II. ADMINISTRATION

         The Plan shall be administered by a committee (the "Committee")
appointed by the Board of Directors of the Company (the "Board"), and the
Committee shall be comprised solely of one or more members of the Board. The
Committee shall have sole authority to select the Optionees from among those
individuals eligible hereunder and to establish the number of shares which may
be issued under each Option. In selecting the Optionees from among individuals
eligible hereunder and in establishing the number of shares that may be issued
under each Option, the Committee may take into account the nature of the
services rendered by such individuals, their present and potential contributions
to the Company's success and such other factors as the Committee in its
discretion shall deem relevant. The Committee is authorized to interpret the
Plan and may from time to time adopt such rules and regulations, consistent with
the provisions of the Plan, as it may deem advisable to carry out the Plan. All
decisions made by the Committee in selecting the Optionees, in establishing the
number of shares which may be issued under each Option and in construing the
provisions of the Plan shall be final.

                             III. OPTION AGREEMENTS

          (a) Each Option shall be evidenced by a written agreement between the
Company and the Optionee ("Option Agreement") which shall contain such terms and
conditions as may be approved by the Committee. The terms and conditions of the
respective Option Agreements need not be identical. Specifically, an Option
Agreement may provide for the surrender of the right to purchase shares under
the Option in return for a payment in cash or shares of Stock or a combination
of cash and shares of Stock equal in value to the excess of the fair market
value of the shares with respect to which the right to purchase is surrendered
over the option price

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therefor ("Stock Appreciation Rights"), on such terms and conditions as the
Committee in its sole discretion may prescribe; provided, that, except as
provided in Subparagraph VIII(c) hereof, the Committee shall retain final
authority (i) to determine whether an Optionee shall be permitted, or (ii) to
approve an election by an Optionee, to receive cash in full or partial
settlement of Stock Appreciation Rights. Moreover, an Option Agreement may
provide for the payment of the option price, in whole or in part, by the
delivery of a number of shares of Stock (plus cash if necessary) having a fair
market value equal to such option price.

         (b) For all purposes under the Plan, the fair market value of a share
of Stock on a particular date shall be equal to the mean of the high and low
sales prices of the Stock (i) reported by the National Market System of NASDAQ
on that date or (ii) if the Stock is listed on a national stock exchange,
reported on the stock exchange composite tape on that date; or, in either case,
if no prices are reported on that date, on the last preceding date on which such
prices of the Stock are so reported. If the Stock is traded over the counter at
the time a determination of its fair market value is required to be made
hereunder, its fair market value shall be deemed to be equal to the average
between the reported high and low or closing bid and asked prices of Stock on
the most recent date on which Stock was publicly traded. In the event Stock is
not publicly traded at the time a determination of its value is required to be
made hereunder, the determination of its fair market value shall be made by the
Committee in such manner as it deems appropriate.

         (c) Each Option and all rights granted thereunder shall not be
transferable other than (i) by will or the laws of descent and distribution,
(ii) pursuant to a qualified domestic relations order as defined by the Code or
Title I of the Employee Retirement Income Security Act of 1974, as amended, or
the rules thereunder, or (iii) with the consent of the Committee. Unless
otherwise determined by the Committee, an Option shall be exercisable during the
Optionee's lifetime only by the Optionee or the Optionee's guardian or legal
representative.

                           IV. ELIGIBILITY OF OPTIONEE

         Options may be granted only to individuals who are employees or
consultants of the Company or any affiliate of the Company at the time the
Option is granted; provided, however, that an individual who is an officer
and/or a director of the Company shall not be eligible to receive an Option
under the Plan even if such individual is also an employee or consultant of the
Company or any affiliate of the Company. Options may be granted to the same
individual on more than one occasion. For all purposes under the Plan, the term
"affiliate" shall mean any corporation, partnership, limited liability company
or partnership, association, trust or other organization which, directly or
indirectly, controls, is controlled by, or is under common control with, the
Company. For purposes of the preceding sentence, "control" (including, with
correlative meanings, the terms "controlled by" and "under common control
with"), as used with respect to any entity or organization, shall mean the
possession, directly or indirectly, of the power (i) to vote more than 50% of
the securities having ordinary voting power for the election of directors of the
controlled entity or organization, or (ii) to direct or cause the direction of
the management and policies of the controlled entity or organization, whether
through the ownership of voting securities or by contract or otherwise.

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                          V. SHARES SUBJECT TO THE PLAN

         The aggregate number of shares which may be issued under Options
granted under the Plan shall not exceed 600,000 shares of Stock. Such shares
may consist of authorized but unissued shares of Stock or previously issued
shares of Stock reacquired by the Company. Any of such shares which remain
unissued and which are not subject to outstanding Options at the termination of
the Plan shall cease to be subject to the Plan, but, until termination of the
Plan, the Company shall at all times make available a sufficient number of
shares to meet the requirements of the Plan. Should any Option hereunder expire
or terminate prior to its exercise in full, the shares theretofore subject to
such Option may again be subject to an Option granted under the Plan. The
aggregate number of shares which may be issued under the Plan shall be subject
to adjustment in the same manner as provided in Paragraph VIII hereof with
respect to shares of Stock subject to Options then outstanding. Exercise of an
Option in any manner, including an exercise involving a Stock Appreciation
Right, shall result in a decrease in the number of shares of Stock which may
thereafter be available, both for purposes of the Plan and for sale to any one
individual, by the number of shares as to which the Option is exercised.

                                VI. OPTION PRICE

         The purchase price of Stock issued under each Option shall be
determined by the Committee, but such purchase price shall not be less than the
fair market value of Stock subject to the Option on the date the Option is
granted. Notwithstanding the foregoing, Options may be granted with a purchase
price that is lower than that specified in the preceding sentence pursuant to a
merger or other corporate transaction.

                                VII. TERM OF PLAN

         The Plan shall be effective upon the date of its adoption by the Board.
Except with respect to Options then outstanding, if not sooner terminated under
the provisions of Paragraph IX, the Plan shall terminate upon and no further
Options shall be granted after the expiration of ten years from the date of its
adoption by the Board.

                    VIII. RECAPITALIZATION OR REORGANIZATION

         (a) The existence of the Plan and the Options granted hereunder shall
not affect in any way the right or power of the Board or the shareholders of the
Company to make or authorize any adjustment, recapitalization, reorganization or
other change in the Company's capital structure or its business, any merger or
consolidation of the Company, any issue of debt or equity securities, the
dissolution or liquidation of the Company or any sale, lease, exchange or other
disposition of all or any part of its assets or business or any other corporate
act or proceeding.

         (b) The shares with respect to which Options may be granted are shares
of Stock as presently constituted, but if, and whenever, prior to the expiration
of an Option theretofore granted, the Company shall effect a subdivision or
consolidation of shares of Stock or the

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payment of a stock dividend on Stock without receipt of consideration by the
Company, the number of shares of Stock with respect to which such Option may
thereafter be exercised (i) in the event of an increase in the number of
outstanding shares shall be proportionately increased, and the purchase price
per share shall be proportionately reduced, and (ii) in the event of a reduction
in the number of outstanding shares shall be proportionately reduced, and the
purchase price per share shall be proportionately increased.

         (c) If the Company recapitalizes, reclassifies its capital stock, or
otherwise changes its capital structure (a "recapitalization"), the number and
class of shares of Stock covered by an Option theretofore granted shall be
adjusted so that such Option shall thereafter cover the number and class of
shares of stock and securities to which the Optionee would have been entitled
pursuant to the terms of the recapitalization if, immediately prior to the
recapitalization, the Optionee had been the holder of record of the number of
shares of Stock then covered by such Option. If (i) the Company shall not be the
surviving entity in any merger, consolidation or other reorganization (or
survives only as a subsidiary of an entity), (ii) the Company sells, leases or
exchanges all or substantially all of its assets to any other person or entity,
(iii) the Company is to be dissolved and liquidated, (iv) any person or entity,
including a "group" as contemplated by Section 13(d)(3) of the Securities
Exchange Act of 1934, as amended, acquires or gains ownership or control
(including, without limitation, power to vote) of more than 50% of the
outstanding shares of the Company's voting stock (based upon voting power), or
(v) as a result of or in connection with a contested election of directors, the
persons who were directors of the Company before such election shall cease to
constitute a majority of the Board (each such event is referred to herein as a
"Corporate Change"), no later than (a) ten days after the approval by the
shareholders of the Company of such merger, consolidation, reorganization, sale,
lease or exchange of assets or dissolution or such election of directors or (b)
thirty days after a change of control of the type described in Clause (iv), the
Committee, acting in its sole discretion without the consent or approval of any
Optionee, shall act to effect one or more of the following alternatives, which
may vary among individual Optionees and which may vary among Options held by any
individual Optionee: (1) accelerate the time at which Options then outstanding
may be exercised so that such Options may be exercised in full for a limited
period of time on or before a specified date (before or after such Corporate
Change) fixed by the Committee, after which specified date all unexercised
Options and all rights of Optionees thereunder shall terminate, (2) require the
mandatory surrender to the Company by selected Optionees of some or all of the
outstanding Options held by such Optionees (irrespective of whether such Options
are then exercisable under the provisions of the Plan) as of a date, before or
after such Corporate Change, specified by the Committee, in which event the
Committee shall thereupon cancel such Options and the Company shall pay to each
Optionee an amount of cash per share equal to the excess, if any, of the amount
calculated in Subparagraph (d) below (the "Change of Control Value") of the
shares subject to such Option over the exercise price(s) under such Options for
such shares, (3) make such adjustments to Options then outstanding as the
Committee deems appropriate to reflect such Corporate Change (provided, however,
that the Committee may determine in its sole discretion that no adjustment is
necessary to Options then outstanding) or (4) provide that the number and class
of shares of Stock covered by an Option theretofore granted shall be adjusted so
that such Option shall thereafter cover the number and class of shares of stock
or other securities or property (including, without limitation, cash) to which
the Optionee would have been entitled pursuant to the terms of the agreement of
merger,

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consolidation or sale of assets and dissolution if, immediately prior to such
merger, consolidation or sale of assets and dissolution, the Optionee had been
the holder of record of the number of shares of Stock then covered by such
Option.

         (d) For the purposes of clause (2) in Subparagraph (c) above, the
"Change of Control Value" shall equal the amount determined in clause (i), (ii)
or (iii), whichever is applicable, as follows: (i) the per share price offered
to shareholders of the Company in any such merger, consolidation,
reorganization, sale of assets or dissolution transaction, (ii) the price per
share offered to shareholders of the Company in any tender offer or exchange
offer whereby a Corporate Change takes place, or (iii) if such Corporate Change
occurs other than pursuant to a tender or exchange offer, the fair market value
per share of the shares into which such Options being surrendered are
exercisable, as determined by the Committee as of the date determined by the
Committee to be the date of cancellation and surrender of such Options. In the
event that the consideration offered to shareholders of the Company in any
transaction described in this Subparagraph (d) or Subparagraph (c) above
consists of anything other than cash, the Committee shall determine the fair
cash equivalent of the portion of the consideration offered which is other than
cash.

         (e) Any adjustment provided for in Subparagraphs (b) or (c) above shall
be subject to any required shareholder action.

         (f) Except as hereinbefore expressly provided, the issuance by the
Company of shares of stock of any class or securities convertible into shares of
stock of any class, for cash, property, labor or services, upon direct sale,
upon the exercise of rights or warrants to subscribe therefor, or upon
conversion of shares or obligations of the Company convertible into such shares
or other securities, and in any case whether or not for fair value, shall not
affect, and no adjustment by reason thereof shall be made with respect to, the
number of shares of Stock subject to Options theretofore granted or the purchase
price per share.

                    IX. AMENDMENT OR TERMINATION OF THE PLAN

         The Board in its discretion may terminate the Plan at any time with
respect to any shares for which Options have not theretofore been granted. The
Board shall have the right to alter or amend the Plan or any part thereof from
time to time; provided, that no change in any Option theretofore granted may be
made which would impair the rights of the Optionee without the consent of such
Optionee.

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                               X. SECURITIES LAWS

         The Company shall not be obligated to issue any Stock pursuant to any
Option granted under the Plan at any time when the offering of the shares
covered by such Option have not been registered under the Securities Act of 1933
and such other state and federal laws, rules or regulations as the Company or
the Committee deems applicable and, in the opinion of legal counsel for the
Company, there is no exemption from the registration requirements of such laws,
rules or regulations available for the offering and sale of such shares.

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