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                       SECURITIES AND EXCHANGE COMMISSION
                              Washington, D.C. 20549

                                  ------------

                                    FORM 8-K/A

                                 AMENDMENT NO. 1

                                 CURRENT REPORT
                     PURSUANT TO SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934


Date of report (date of earliest event reported):      March 12, 1998        
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                             ASPEN TECHNOLOGY, INC.
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             (Exact name of registrant as specified in its charter)


         DELAWARE                     0-24786                  04-2739697
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(State or other jurisdiction        (Commission              (IRS employer
     of incorporation)              file number)           identification no.)


TEN CANAL PARK, CAMBRIDGE, MASSACHUSETTS                               02141
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(Address of principal executive offices)                            (Zip code)


Registrant's telephone number, including area code:     (617) 949-1000
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                                 NOT APPLICABLE
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          (Former name or former address, if changed since last report)


         The undersigned registrant hereby amends the following items, exhibits
and portions of its Current Report on Form 8-K (dated as of March 26, 1998) as
set forth in the pages attached hereto:


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ITEM 5.     OTHER EVENTS.

         On March 12, 1998, Aspen Technology, Inc., a Massachusetts corporation
("Aspen Massachusetts"), changed its state of incorporation by merging with and
into Aspen Technology, Inc., a Delaware corporation and wholly owned subsidiary
of Aspen Massachusetts ("Aspen Delaware" or the "Company"). The reincorporation
was approved by the stockholders of Aspen Massachusetts at the 1997 Annual
Meeting of Stockholders held on December 23, 1997. The Certificate of
Incorporation and By-Laws of Aspen Delaware were included as exhibits to the
Current Report on Form 8-K being amended hereby.

      In connection with the reincorporation, the Board of Directors of Aspen
Delaware determined to adopt a stockholder rights plan equivalent to the
stockholder rights plan adopted by the Board of Directors of Aspen Massachusetts
on October 9, 1997. On March 12, 1998 the Board of Directors of the Company
declared a dividend of one right (each a "Right" and collectively the "Rights")
for each outstanding share of common stock, par value $.10 per share, of the
Company (the "Common Shares"). The Rights were issued to the holders of record
of Common Shares outstanding on March 12, 1998 and have been and will be issued
with respect to Common Shares issued thereafter until the Distribution Date (as
defined below) and, in certain circumstances, with respect to Common Shares
issued after the Distribution Date. Each Right, when it becomes exercisable as
described below, will entitle the registered holder to purchase from the Company
one one-hundredth (1/100th) of a share of Series A participating cumulative
preferred stock, $.10 par value per share, of the Company (the "Preferred
Shares") at a price of $175.00 (the "Purchase Price"). The description and terms
of the Rights are set forth in a rights agreement dated as of March 12, 1998
(the "Rights Agreement") between the Company and American Stock Transfer and
Trust Company, as rights agent (the "Rights Agent"). THE TERMS OF THE RIGHTS
AGREEMENT ARE SUBSTANTIALLY EQUIVALENT TO THE TERMS OF A RIGHTS AGREEMENT DATED
AS OF OCTOBER 9, 1997 BETWEEN ASPEN MASSACHUSETTS AND AMERICAN STOCK TRANSFER
AND TRUST COMPANY, AS RIGHTS AGENT.

         Pursuant to Rule 12g-3(a) under the Securities Exchange Act of 1934, as
amended (the "Exchange Act"), the Aspen Delaware Common Stock and the Rights are
deemed to be registered under Section 12(g) of the Exchange Act.

         Until the earlier of (i) such time as the Company learns that a person
or group (including any affiliate or associate of such person or group)
acquired, or obtained the right to acquire, beneficial ownership of 15% or more
of the outstanding Common Shares (such person or group being called an
"Acquiring Person") or (ii) such date, if any, as may be designated by the Board
of Directors of the Company following the commencement of, or first public
disclosure of an intent to commence, a tender or exchange offer for outstanding
Common Shares which could result in the offeror becoming the beneficial owner of
15% or more of the outstanding Common Shares (the earlier of such dates being
called the "Distribution Date"), the Rights will be evidenced by the
certificates for Common Shares registered in the names of the holders thereof
(which certificates for Common Shares shall also be deemed to be Right
Certificates, as defined below) and not by separate Right Certificates.
Therefore, until the Distribution Date, the Rights will be transferred with and
only with the Common Shares.

         As soon as practicable following the Distribution Date, separate
certificates evidencing the Rights ("Right Certificates") will be mailed to
holders of record of the Common Shares as of the close of business on the



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Distribution Date (and to each initial record holder of certain Common Shares
originally issued after the Distribution Date), and such separate Right
Certificates alone will thereafter evidence the Rights. The Rights are not
exercisable until the Distribution Date and will expire on March 12, 2008 (the
"Expiration Date"), unless earlier redeemed by the Company as described below.

         To preserve the actual or potential economic value of the Rights, the
number of Preferred Shares or other securities issuable upon exercise of a
Right, the Purchase Price and Redemption Price and the number of Rights
associated with each outstanding Common Share are all subject to adjustment by
the Board of Directors as provided in the Rights Agreement in the event of any
change in the Common Shares or Preferred Shares, whether by reason of stock
dividends, stock splits, recapitalizations, mergers, consolidations,
combinations or exchanges of securities, split-ups, split-offs, spin-offs,
liquidations, other similar changes in capitalization, any distribution or
issuance of cash, assets, evidences of indebtedness or subscription rights,
options or warrants to holders of Common Shares or Preferred Shares, as the case
may be (other than distribution of the Rights or regular quarterly cash
dividends) or otherwise.

         The Preferred Shares are authorized to be issued in fractions which are
an integral multiple of one one-hundredth (1/100th) of a Preferred Share. The
Company may, but is not required to, issue fractions of shares upon the exercise
of Rights, and, in lieu of fractional shares, the Company may issue certificates
or utilize a depository arrangement as provided by the terms of the Preferred
Shares and, in the case of fractions other than one one-hundredth (1/100th) of a
Preferred Share or integral multiples thereof, may make a cash payment based on
the market price of such shares.

         Upon a person or a group becoming an Acquiring Person, the Rights will
entitle each holder of a Right to purchase, for the Purchase Price, that number
of one one-hundredths (1/100ths) of a Preferred Share equivalent to the number
of Common Shares which at the time of the transaction would have a market value
of twice the Purchase Price.

         In the event the Company is acquired in a merger or other business
combination or 50% or more of its assets or assets representing 50% or more of
its earning power are sold, leased, exchanged or otherwise transferred (in one
or more transactions) to a publicly traded corporation, each Right will entitle
its holder to purchase, for the Purchase Price, that number of common shares of
such corporation which at the time of the transaction would have a market value
of twice the Purchase Price. In the event the Company is acquired in a merger or
other business combination or 50% or more of its assets or assets representing
50% or more of the earning power of the Company are sold, leased, exchanged or
otherwise transferred (in one or more transactions) to an entity that is not a
publicly traded corporation, each Right will entitle its holder to purchase, for
the Purchase Price, at such holder's option, (i) that number of shares of such
entity (or, at such holder's option, of the surviving corporation in such
acquisition, which could be the Company) which at the time of the transaction
would have a book value of twice the Purchase Price or (ii) if such entity has
an affiliate which has publicly traded common shares, that number of common
shares of such affiliate which at the time of the transaction would have a
market value of twice the Purchase Price.

         Any Rights that are at any time beneficially owned by an Acquiring
Person (or any affiliate or associate of an Acquiring Person) shall be null 



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and void and nontransferable, and any holder of any such Right (including any
purported transferee or subsequent holder) shall not have any right to exercise
or transfer any such right.

         At any time after a person or a group becomes an Acquiring Person, the
Board of Directors of the Company may exchange all or part of the then
outstanding Rights (other than Rights that have become null and void and
nontransferable as described above) for consideration per Right consisting of
one-half of the securities that otherwise would have been issuable to the holder
of each Right upon exercise thereof. The Board of Directors of the Company may
also issue, in substitution for Preferred Shares, Common Shares having an
equivalent market value to the Preferred Shares if, at such time, the Company
has a sufficient number of Common Shares issued but not outstanding or
authorized but unissued.

         At any time prior to the earlier of (i) such time as a person becomes
an Acquiring Person and (ii) the Expiration Date, the Board of Directors of the
Company may redeem the Rights in whole, but not in part, at a price (in cash or
Common Shares or other securities of the Company deemed by the Board of
Directors to be at least equivalent in value) of $.01 per Right (the "Redemption
Price").

         Immediately upon the action of the Board of Directors of the Company
electing to redeem the Rights, the Company shall make an announcement thereof,
and, upon such election, the right to exercise the Rights will terminate and the
only right of the holders of Rights will be to receive the Redemption Price.

         Until a Right is exercised, the holder thereof, as such, will have no
rights therefrom as a stockholder of the Company, including, without limitation,
the right to vote or to receive dividends.

         At any time prior to the Distribution Date, the Company may, without
the approval of any holder of the Rights, supplement or amend any provision of
the Rights Agreement (including the date on which the Distribution Date shall
occur, the time during which the Rights may be redeemed or the terms of the
Preferred Shares), except that no supplement or amendment shall be made which
reduces the Redemption Price or provides for an earlier Expiration Date.

         The Rights have certain antitakeover effects. The Rights will cause
substantial dilution to a person or group that attempts to acquire the Company
without conditioning the offer on substantially all the Rights being acquired.
The Rights will not interfere with any merger or other business combination or
with a third party approved by the Board of Directors of the Company since the
Board of Directors of the Company may, at its option, at any time prior to any
person becoming an Acquiring Person, redeem all but not less than all of the
then outstanding Rights at the Redemption Price.

         The Rights Agreement specifying the terms of the Rights, the
Certificate of Designation of the Preferred Shares specifying the terms of the
Preferred Shares (Exhibit A to the Rights Agreement) and the form of Right
Certificate (Exhibit B to the Rights Agreement) were filed as exhibits to the
Current Report on Form 8-K being amended hereby. The foregoing description of
the Rights does not purport to be complete and is qualified in its entirety by
reference to such exhibits, which are incorporated herein by reference.



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                                   SIGNATURES

         Pursuant to the requirements of the Securities Exchange Act of 1934,
the registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.


                                       ASPEN TECHNOLOGY, INC.


Date: June 10, 1998                    By: /s/ Mary A. Palermo
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                                           Mary A. Palermo
                                           Executive Vice President, Finance and
                                           Chief Financial Officer