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                                                                    Exhibit 10.8


                           PLATINUM technology, inc.
                             AMENDED AND RESTATED
                             EMPLOYMENT AGREEMENT
                             --------------------
                                        


     This Amended and Restated Agreement ("Agreement"), is made and entered into
as of the 28th day of October, 1997 (the "Effective Date"), by and between
Platinum technology, inc., a Delaware corporation (the "Company"), and Paul L.
Humenansky (the "Executive").

     WHEREAS, the Company entered into an Employment Agreement with Executive as
an executive employee dated as of March 1, 1991 and the parties believe that the
Employment Agreement needs to be clarified and the parties deem it advisable to
amend and restate the Employment Agreement to clarify the language and include
certain provisions which should have been included;

     NOW, THEREFORE, in consideration of the mutual covenants and agreements
contained herein, and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereby agree as
follows:

1.   Employment of Executive
     -----------------------

     As of the Effective Date, the Company hereby engages and employs Executive
in an executive capacity as the Company's Chief Operating Officer and Executive
hereby accepts such employment and agrees to act as an employee of the Company
in accordance with the terms of employment hereinafter specified ("Executive
Employment").

2.   Term of Executive Employment
     ----------------------------

     The period of Executive Employment shall begin on the Effective Date and
continue until terminated as hereinafter provided (the "Employment Period").

3.   Duties
     ------

     (a) Executive shall be employed by Company as the Company's Chief Operating
Officer. In such capacity, Executive shall have supervision and control over,
and responsibility for, the general management of the development laboratories
and of the research, development and production of new products of the Company,
and shall have such other powers and duties as the Chief Executive Officer
and/or the Board of Directors of the Company may from time to time prescribe;
provided that, such powers and duties are consistent with the Executive's then
present duties and with his position as the Company's senior executive officer
in charge of the new product development and management of the development
laboratories of the Company.

     (b) Nothing contained herein shall be construed so as to prohibit Executive
from performing such other or additional duties or responsibilities, and
exercising such other or

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additional authority in furtherance of the goals of the Company, as the
Executive and Chief Executive Officer and/or the Board of Directors of the
Company shall from time to time agree upon.

     (c) Executive shall devote such portion of his business time and attention
as is necessary to appropriately and efficiently discharge his duties and
responsibilities as herein set forth. If Executive so discharges his duties he
may engage in other business and civic activities, in addition to those relating
to the Company's business, if such activities are not otherwise prohibited by
the terms of this Agreement.

     (d) During Executive's employment hereunder, Executive shall not be
required to relocate his principal residence from his current location as a
result of the Company moving its principal executive offices or the Executive's
office to an address greater than twenty (20) miles away from the Company's
principal executive offices (or the Executive's office) at the Effective Date
and shall not be required to perform services which could make the continuance
of Executive's principal residence in such location unreasonably difficult or
inconvenient for Executive except to the extent that the performance of such
services (and travel) is commensurate with Executive's duties specified
hereunder.

4.   Executive Salary and Compensation:
     --------------------------------- 

     (a) Base Salary. During the Employment Period the Company shall pay or
cause to be paid to Executive an initial base salary ("Base Salary") at an
annual rate of $508,000.00 per year, payable to Executive on a periodic basis in
accordance with the Company's then current executive salary payment practice;
provided, however, that the installments may not be made less frequently than on
a month basis. Such Base Salary shall be subject to review in accordance with
the Company's normal practice for executive salary review from time to time in
effect, and will not be reduced without the prior written consent of Executive.

     (b) Incentive Compensation. Executive shall be entitled to receive an
annual bonus for the Employment Period as determined by the Compensation
Committee of the Company's Board of Directors (the "Committee") for each fiscal
year of the Company during the Employment Period ("Incentive Compensation"). The
Incentive Compensation for 1996 shall be the amounts set forth in Exhibit A
hereto, which may be amended from time to time by the Committee (computed before
deduction of the bonus payable to Executive hereunder and any bonus payable to
any executive officer which is also based upon the Company's pre-tax income);
provided, however, if the aggregate amount which is payable pursuant to this
Section 4(b) for any one calendar year shall exceed $1,000,000 then amounts
payable in excess of $1,000,000 shall be determined by a formula to be
established by the Committee. It is the intention of the parties hereto, that in
connection with establishing Incentive Compensation for periods following 1997
the Committee will not act arbitrarily and will modify the initial formula for
incentive compensation in good faith in light of the Company's and the
Executive's performance. The Company will pay the 1997 Incentive Compensation to
Executive based upon the audited financial statements of the Company prepared by
a nationally known independent accounting firm regularly retained by the Company
("Accounting Firm") (within 30 days following completion of the Company's annual
audit and in accordance with the final determination of Incentive Compensation
payable made by the aforementioned Accounting Firm). If Executive's employment
is terminated effective at any time other than the end of the Company's fiscal
year,

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the final adjustments will be made by the Accounting Firm based upon the most
recent unaudited financial statements of the Company for the month end
immediately prior to the effective date of termination.

     (c) Withholding of Certain Taxes. All compensation referred to in Section
4(a) and 4(b) of this Agreement is stated in terms of gross amount, it being
understood that the Company will be required to withhold from such gross amount
deductions for federal, state and local income taxed (if any), F.I.C.A.,
unemployment compensation taxes and the like.

     (d) Fringe Benefits. During the Employment Period, the Company shall
provide the following fringe benefits (hereinafter collectively "Fringe
Benefits") to Executive: (i) Medical and Dental Insurance. The Company shall
provide Executive and Executives's immediate family, including spouse and
children, if any, at the Company's expense, with comprehensive medical and
dental insurance coverage similar to that provided to other executive officers
of the Company; (ii) Life Insurance. The Company shall provide Executive, at the
Company's expense, (a) a term and/or whole life policy or policies of insurance
insuring the life of Executive for the benefit of person(s) designated from time
to time by Executive in the amount of up to Five Million Dollars ($5,000,000)
and shall be a sole life policy if requested by Executive, which shall be
assigned to Executive, together with any cash value thereof at Executive's
request and (b) a split dollar life insurance policy or policies insuring the
life of Executive for the benefit of the person(s) designated from time to time
by Executive in a base amount of not less than Six Million Dollars ($6,000,000)
and the premiums therefor are reimbursed to the Company upon death or
termination of employment and transfer of policy to Executive as more
particularly described in such policy; (iii) Disability Insurance. The Company
shall provide Executive, at the Company's expense, with comprehensive short and
long term disability insurance in an amount which the Company determines is
reasonably commensurate with Executive's compensation contemplated hereunder,
including, without limitation, Executive's base salary, incentive compensation,
fringe benefits and the like; (iv) Clubs; Professional Organizations. The
Company shall pay the annual dues and assessments for the Executive's membership
in the DuPage Club, Glen Oak Country Club, Central Park Athletic Club and YEO
("Clubs"); (v) Automobile. The Company shall provide Executive with the use of
Company car(s) (such car(s) to be comparable to the car(s) the Company provides
on the date hereof) and shall reimburse Executive for all related expenses,
including insurance coverage related thereto; (vi) Administrative Assistance.
The Company shall at the Company's expense maintain his same office at the
Corporate headquarters and provide Executive with an Administrative Assistant
and such other clerical assistance as required by Executive.

5.  Expenses. The Company shall pay or reimburse Executive in accordance with
the Company's policy for all expenses reasonably incurred by Executive during
the period of Executive's employment in connection with the performance of
Executive's duties under this Agreement, including, without limitation, travel,
entertainment and automobile expenses. As the Company may reasonably request,
Executive shall provide to the Company documentation or supporting information
relating to the expenses for which Executive seeks reimbursement.

6.  For purposes of Sections 7, 8 and 9 the amount of annual Incentive
Compensation and Base Salary which is payable as severance shall be equal to the
greatest amount of Incentive Compensation and Base Salary, respectively, paid to
Executive during any trailing 12 month period during the 36 month period
preceding termination of Executive's employment with the Company (the "Severance
Pay"). In addition to the foregoing, at the end of the Severance

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Period, Payout Period, CIC Period or such earlier date as provided by Section
9(b), at the Executive's request, the Company shall (1), at no cost to
Executive, transfer its right, title and interest in (a) any airline travel pass
purchased for the benefit of the Executive (including but not limited to the
United Airlines Lifetime Limited Pass Plus Number P10194680002; (b) all office
equipment, computer, computer accessories, furniture, software, modem, fax
machine, printers and related equipment supplied by the Company for the
Executive's offices including his home office; and (c) the memberships to the
Clubs; and (2) (a) sell to Executive any automobile or other vehicle provided to
Executive pursuant to Section 4(d) at the net book value or (b) assign any
automobile lease for the vehicle(s) to the Executive, provided Executive assumes
all remaining lease payments thereunder. If during the Severance Period and
Payout Period (as hereinafter defined) the Executive's term as a director of the
Company expires, the Company shall nominate and recommend to the shareholders of
the Company the election of the Executive for the office of director of the
Company.

7.   Termination of Executive Employment by the Company: The Company shall have
the option to terminate Executive's employment with or without cause, for any
reason whatsoever, including without limitation, Disability (as hereinafter
defined) by providing written Notice of Termination (as defined below) to
Executive and such termination shall be effective 10 days after the giving of
said written notice; provided, however, but subject in all events to Section 9
hereof, (i) if Executive is terminated for any reason other than Good Cause then
the Company shall continue to pay to Executive, the Severance Pay, Fringe
Benefits and the like, for a period of 3 years from the effective date of
Executive's termination ("Payout Period"), and (ii) if Executive is terminated
for Good Cause, the Company shall pay to Executive all such compensation owing
through the date of termination.

     For purposes of this Section 7, Notice of Termination shall mean delivery
to Executive of a copy of a resolution duly adopted by the affirmative vote of
not less than a majority of the entire membership of the Company's Board of
Directors at a meeting of the Board of Directors (after reasonable notice has
been delivered to Executive and reasonable opportunity has been provided for
Executive, together with Executive's counsel, to be heard before the Board of
Directors prior to such vote.) For purposes of this Agreement, the termination
of the Executive's employment hereunder shall be deemed to have been for Good
Cause only if the termination of the Executive's employment shall have been the
result of (a) an act or acts of dishonesty by Executive which the Board of
Directors reasonably believes constitute a felony which result directly or
indirectly in gain to or personal enrichment of the Executive at the Company's
expense, or (b) an act or acts by Executive which the Board of Directors
reasonably believes constitute a felony and as a result of which the continued
employment of executive by the Company will have an adverse effect on the
Company's business.

8.   Termination of Executive Employment by Executive. The Executive may
terminate the Executive's employment by the Company at any time, and in such
event, unless prior to giving his notice, Executive shall have received a Notice
of Termination for Good Cause, the Company shall continue to pay to Executive,
as severance compensation, all compensation payable, including Severance Pay,
Fringe Benefits and the like for period of 18 months from the effective date of
Executive's termination (the "Severance Period") but subject in all events to
Section 9 hereof.

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9.   Change in Control.

     (a) For purposes hereof a "Section 9 Termination" shall have occurred if
Executive's employment is terminated by Executive, or by the Company other than
for Good Cause, at any time during the period beginning on the 120th day
preceding the occurrence of a change in control (hereinafter defined) of the
Company and ending on the second anniversary following the occurrence of a
change in control of the Company. For purposes of this Agreement, a "change in
control" of the Company shall be deemed to have occurred on the first of any of
the following dates:

     (1) The acquisition by any individual, entity or group (within the meaning
     of Section 13(d)(3) or 14(d)(2) of the Securities Exchange Act of 1934, as
     amended (the "Exchange Act")) (a "Person") of beneficial ownership (within
     the meaning of Rule 13d-3 promulgated under the Exchange Act) of twenty
     percent (20%) or more of either (A) the then-outstanding shares of common
     stock of the Company (the "Outstanding Company Common Stock") or (B) the
     combined voting power of the then-outstanding voting securities of the
     Company entitled to vote generally in the election of directors (the
     "Outstanding Company Voting Securities"); provided, however, that for
     purposes of this subsection (i), the following acquisitions shall not
     constitute a Change of Control: (A) any acquisition directly from the
     Company other than in connection with the acquisition by the Company or its
     affiliates of a business, (B) any acquisition by the Company, (C) any
     acquisition by any employee benefit plan (or related trust) sponsored or
     maintained by the Company or any corporation controlled by the Company, (D)
     any acquisition by a lender to the Company pursuant to a debt restructuring
     of the Company, or (E) any acquisition by any corporation pursuant to a
     transaction which complies with clauses (A), (B) and (C) of subsection
     (iii) of this Section 2(d);

     (2) Individuals who, as of the date hereof, constitute the Board (the
     "Incumbent Board") cease for any reason to constitute at least a majority
     of the Board; provided, however, that any individual becoming a director
     subsequent to the date hereof whose election, or nomination for election by
     the Company's shareholders, was approved by a vote of at least a majority
     of the directors then comprising the Incumbent Board shall be considered as
     though such individual were a member of the Incumbent Board, but excluding,
     for this purpose, any such individual whose initial assumption of office
     occurs as a result of an actual or threatened election contest with respect
     to the election or removal of directors or other actual or threatened
     solicitation of proxies or consents by or on behalf of a Person other than
     the Board;

     (3) Consummation of a reorganization, merger or consolidation of the
     Company or any direct or indirect subsidiary of the Company or sale or
     other disposition of all or substantially all of the assets of the Company
     (a "Business Combination"), in each case, unless, following such Business
     Combination, (A) all or substantially all of the individuals and entities
     who were the beneficial owners, respectively, of the Outstanding Company
     Common Stock and Outstanding Company Voting Securities immediately prior to
     such Business

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     Combination beneficially own, directly or indirectly, more than sixty
     percent (60%) of, respectively, the then-outstanding shares of common stock
     and the combined voting power of the then outstanding voting securities
     entitled to vote generally in the election of directors, as the case may
     be, of the corporation resulting from such Business Combination (which
     shall include for these purposes, without limitation, a corporation which
     as a result of such transaction owns the Company or all or substantially
     all of the Company's assets either directly or through one or more
     subsidiaries) in substantially the same proportions as their ownership,
     immediately prior to such Business Combination of the Outstanding Company
     Common Stock and Outstanding Company Voting Securities, as the case may be,
     (B) no Person (excluding any corporation resulting from such Business
     Combination or any employee benefit plan (or related trust) of the Company
     or such corporation resulting from such Business Combination and any Person
     beneficially owning, immediately prior to such Business Combination,
     directly or indirectly, 20% or more of the Outstanding Common Stock or
     Outstanding Voting Securities, as the case may be) beneficially owns,
     directly or indirectly, twenty percent (20%) or more of, respectively, the
     then outstanding shares of common stock of the corporation resulting from
     such Business Combination, or the combined voting power of the then
     outstanding voting securities of such corporation entitled to vote
     generally in the election of directors and (C) at least a majority of the
     members of the board of directors of the corporation resulting from such
     Business Combination were members of the Incumbent Board at the time of the
     execution of the initial agreement, or of the action of the Board,
     providing for such Business Combination; or

     (4) Approval by the shareholders of the Company of a complete liquidation
     or dissolution of the Company other than to a corporation which would
     satisfy the requirements of clauses (A), (B) and (C) of Subsection (iii) of
     this Section 2(d), assuming for this purpose that such liquidation or
     dissolution was a Business Combination.

     (b) If a Section 9 Termination occurs, then notwithstanding the provisions
of Section 7 and 8 hereof, the Company shall continue to pay to Executive, as
severance compensation, the Severance Pay and Fringe Benefits for a period of
five years from the effective date of Executive's termination (the "CIC
Period"). In lieu of regular payments of Base Salary during the CIC Period,
Executive shall be entitled to receive, upon Executive's written election, a
lump sum payment equal to the present value of the stream of monthly payments
for the CIC Period, in which each monthly payment is 1/12 of the greatest amount
paid to Executive as Base Salary during any trailing 12 month period in the 36
months prior to Executive's election hereunder. Executive may also similarly
elect to receive a lump sum payment equal to the present value of the Incentive
Compensation under Section 4(b) hereof for the balance of the CIC Period and an
amount equal to the present value of the Fringe Benefits remaining to be paid
for the balance of the CIC Period based upon the Company's expenses for
providing the Fringe Benefits pursuant to Section 4(d) hereof during the
Company's most recently completed fiscal year. For purposes of this computation,
present value shall be calculated on the basis of the prime rate of interest
announced by the Company's principal bank, or if it has no such bank, published
in the Wall Street Journal, on the date of Executive's election to receive the
lump sum payments provided for herein.

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10.  Death or Disability of the Executive: Executive's employment shall
automatically terminate upon the death of the Executive and, at the option of
the Company as determined by the Board of Directors, upon the Disability (as
hereinafter defined) of Executive. "Disability," as used herein, shall be deemed
to have occurred whenever the Board determines, that in its judgment Executive
has suffered physical or mental illness, injury or infirmity of such a nature,
degree or effect as to render Executive, for a significant period of time,
substantially unable to perform his duties as delineated in paragraph 3 hereof.

11.  Gross Up for Excise Tax Liability: If it shall be determined that any
payment or benefit received or to be received by Executive under this Agreement
or any other plan, arrangement or agreement of the Company or any person whose
actions result in a Change in Control of the Company or any affiliate thereof
(all such payments and benefits a "Payment"), would be subject to the excise tax
imposed by Section 4999 of the Internal revenue Code of 1986, as amended (the
"Code") (the "Excise Tax"), then the Company shall pay to Executive an
additional payment (a "Gross-Up Payment") in an amount necessary to reimburse
Executive, on an after-tax basis, for the Excise Tax and for any federal, state
and local income tax and excise tax (including any interest and penalties
imposed with respect to such taxes) that may be imposed by reason of the
Payment. For purposes of determining the amount of any Gross-Up Payment,
Executive shall be deemed to pay federal, state and local income taxes at the
highest applicable marginal rate of taxation in the calendar year in which the
Gross-Up Payment is to be made. All determinations required to be made under
this Section 11, including whether a Gross-Up Payment is required and the amount
of such Gross-Up Payment shall be made by the Accounting Firm which shall
provide detailed supporting calculations both to the Company and Executive
within 15 business days of the request for such determination. Such request may
be made by either party. The Company shall pay the fees and expenses of the
Accounting Firm in connection with any determinations hereunder. The Gross-Up
Payment shall be paid by the Company within 10 days of the Accounting Firm's
determination of the amount thereof.

12.  Non-Compete: In the event Executive terminates his employment pursuant to
Section 8 hereof, Executive hereby agrees that, during the Severance Period he
shall not, directly or indirectly, as employee, agent, consultant, stockholder,
director, co-partner or in any other individual or representative capacity, own,
operate, manage, control, invest in or participate in any manner in, act as a
consultant or advisor to, render services for (alone or in association with any
person, firm, corporation or entity), or otherwise assist Computer Associates
International, Inc., BMC Software Inc., and/or Rational Software ("Competitor");
provided, however, that nothing contained herein shall be construed to prevent
Executive from investing in the stock of a Competitor, but only if Executive is
not involved in the business of said Competitor and if Executive and his
associates (as such term is defined in Regulation 14(A) promulgated under the
Securities Exchange Act of 1934, as in effect on the date hereof), collectively,
do not own more than an aggregate of two (2%) percent of the stock of such
Competitor."

13.  Mitigation of Amounts Payable Under Sections 7, 8 and 9: The Executive
shall not be required to mitigate the amount of any payment provided for
pursuant to Sections 7, 8 and 9 of this Agreement by seeking other employment or
otherwise, and, further, any payment or benefit to be provided to Executive
pursuant to this Agreement shall not be reduced by any compensation or other
amount earned or collected by Executive at any time before or after the
termination of Executive Employment hereunder.

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14.  Miscellaneous: Any notice or other communication required or permitted
hereunder shall be in writing and shall be deemed given when delivered in person
to the following addresses:

(i)  if to the Company, to:

     Platinum technology, inc.
     1815 South Meyers Road
     Oakbrook Terrace, IL 60181
     Attn:  Chief Executive Officer
     with a copy to:

     Platinum technology, inc.
     1815 South Meyers Road
     Oakbrook Terrace, IL 60181
     Attn: General Counsel

(ii) If to Executive to:

     Paul L. Humenansky
     630 Forest Avenue
     Glen Ellyn, IL 60137

     Any party may change its address for notice hereunder by notice to the
other party hereto.

     (b) Governing Law. The parties agree that this Agreement shall be construed
and governed in accordance with the laws of the State of Illinois applicable to
agreements made and to be performed entirely within such state.

     (c) Binding Effect. This Agreement shall be binding upon and incur to the
benefit of the parties hereto and their respective heirs, legal representatives,
executors, administrators, successors and assigns. Any Successor will
automatically succeed to the obligations of the Company under this Agreement,
including the obligations set forth in Sections 7 and 8 of this Agreement (as
adjusted pursuant to the terms of Section 9 of this Agreement); provided that,
the Company shall remain liable under this Agreement in such event.

     (d) Counterparts. This Agreement may be executed simultaneously in one or
more counterparts, each of which shall be deemed an original but all of which
together shall constitute one and the same instrument.

     (e) Entire Agreement. This Agreement represents the entire agreement and
understanding of the parties hereto with respect to the matters set forth
herein. This Agreement supersedes all prior negotiations, discussions
correspondence, communications, understandings and agreements between the
parties, written or oral, relating to the subject matter of this Agreement. This
Agreement may be amended, superseded, canceled, renewed, or extended and the
terms hereof may be waived, only by a written instrument signed by the parties
hereto or, in the case of a waiver, by the party waiving compliance.

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     (f) Waivers. No delay on the part of any party in exercising any right,
power or privilege hereunder shall operate as a waiver thereof. Nor shall any
waiver on the part of any party of any such right, power or privilege hereunder,
nor any single or partial exercise of any right, power or privilege hereunder,
preclude any other or further exercise thereof or the exercise of any other
right, power or privilege hereunder.

     (g) Headings. The headings in this Agreement are inserted for convenience
only and are not to be considered in the interpretation or construction of the
provisions hereof.

     (h) Arbitration. Except for any claim or dispute which gives rise or could
give rise to equitable relief under this Agreement, at the request of the
Executive any disagreement, dispute, controversy or claim arising out of or
relating to this Agreement or the breach hereof shall be settled exclusively and
finally by arbitration. The arbitration shall be conducted in accordance with
such rules and before such arbitrator as the parties shall agree and if they
fail to so agree within 15 days after demand for arbitration, such arbitration
shall be conducted in accordance with the Commercial Arbitration Rules of the
American Arbitration Association (hereinafter referred to as "AAA Rules"). Such
arbitration shall be conducted in Chicago, Illinois, or in such other city as
the parties to the dispute may designate by mutual consent. The arbitral
tribunal shall consist of three arbitrators (or such lesser number as may be
agreed upon by the parties) selected according to the procedure set forth in the
AAA Rules in effect on the date hereof and the arbitrators shall be empowered to
order any remedy which is appropriate to the proceedings and issues presented to
them. The chairman of the arbitral tribunal shall be appointed by the American
Arbitration Association from among the three arbitrators so selected. Any party
to a decision rendered in such arbitration proceedings may seek an order
enforcing the same by any court having jurisdiction.

     (i) No Strict Construction. The language used in this Agreement will be
deemed to be the language chosen by the Executive and the Company to express
their mutual intent, and no rule of strict construction will be applied against
the Executive or Company.

     (j) Legal Expenses. The Executive shall be entitled to recover any expenses
for attorney's fees and disbursements incurred by him in connection with
enforcing his rights under this Agreement.

     IN WITNESS WHEREOF, the Company and Executive have signed this Agreement as
of the day and year written above.

                                       PLATINUM technology, inc.


                                       By: /s/ Andrew J. Filipowski
                                           ------------------------------

                                       Its: Chief Executive Officer
                                            -----------------------------


                                       /s/ Paul L. Humenansky
                                       ----------------------------------
                                       Paul L. Humenansky


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