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                                                                    Exhibit 10.1

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                              SUBLEASE AGREEMENT

  This Sublease Agreement ("Sublease") is executed as of June 16th, 1998, by
and between APL LAND TRANSPORT SERVICES, INC., a Tennessee corporation
("Sublandlord") and PLATINUM TECHNOLOGY, INC., a Delaware corporation (the
"Subtenant").

                                  WITNESSETH:
                                  -----------
  WHEREAS, Sublandlord is the tenant of the premises demised under a certain
Office Lease dated March 29, 1993, by and between Sublandlord, as tenant, and
LaSalle National Trust, N.A. as Trustee under Trust Agreement dated July 15,
1984 and known as Trust No. 108702, as landlord, which lease is hereinafter
referred to as the "Base Lease."  The term "Landlord" as used herein shall mean
the successors and assigns of the original landlord under the Base Lease.

  WHEREAS, Sublandlord has agreed with Subtenant to sublease to Subtenant a
certain portion of the premises occupied by Sublandlord under the terms of the
Base Lease, upon the terms and conditions herein provided.

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

  1.   Premises.  Sublandlord hereby leases to Subtenant a portion of
those certain premises leased to Sublandlord under the Base Lease (the
"Subleased Premises") consisting of approximately Twenty One Thousand Five
Hundred Seventy Five (21,575) rentable square feet as described and shown on
Exhibit A attached hereto, which Subleased Premises are located on the fourth
(4th) floor of the building commonly known as 1901 South Meyers Road, Oakbrook
Terrace, Illinois (the "Building").  Said designation of the size of the
Subleased Premises shall be determinative between the parties.

  2.   Term of Sublease.  The term of the Sublease shall commence on the
latter of (i) the full execution of this Sublease or (ii) Landlord's delivery of
its consent to this Sublease or the waiver of its right to consent to the same,
by affirmative act or lapse of time, (the "Commencement Date") and shall
terminate on November 14, 1999, unless sooner terminated as provided herein.

  3.   Rental.  (a) As rental for the use of the Subleased Premises,
Subtenant shall pay Monthly Gross Rent to Sublandlord of Twenty One Thousand
Five Hundred Seventy Five and No/100 Dollars ($21,575.00) ($12.00 per rentable
square foot per annum).  Such rental shall be payable in advance on the
Commencement Date and on the first day of each month during the term hereof.
Such rental shall be prorated for 
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partial months within the term hereof.

  (b)  All rentals shall be payable to Sublandlord and shall be delivered to
Sublandlord c/o APL Limited, 6060 Primacy Parkway, Suite 300, Memphis, TN 38119,
Attention: Shelley Carroll or at such location as Sublandlord may from time
to time designate in writing.

  (c)  All charges, costs and sums required to be paid by Subtenant hereunder
shall be deemed to be rent. Subtenant's covenant to pay rent shall be
independent of any other covenant in this Sublease. Rent shall be paid without
any set-off or deduction whatsoever, except as specifically set forth herein.

  (d)  As security for the performance of its obligations under this Sublease,
Subtenant, upon its execution of this Sublease has paid to Sublandlord a
security deposit (the "Security Deposit") in the amount of Thirty Two Thousand
Three Hundred Sixty Two and 50/00 Dollars ($32,362.50). The Security Deposit may
be applied by Sublandlord to cure any default of Subtenant beyond applicable
notice and cure periods and upon notice by Sublandlord of such application,
Subtenant shall replenish the Security Deposit in full by promptly paying to
Sublandlord the amount so applied. Within forty five (45) days after the
Expiration Date, Sublandlord shall return to Subtenant the balance, if any, of
the Security Deposit. The Security Deposit shall not be deemed an advance
payment of Rent or measure of damages for any default by Subtenant under this
Sublease, nor shall it be a bar or defense to any action that Sublandlord may at
any time commence against Subtenant. Sublandlord shall not be required to
segregate the Security Deposit from its general funds. Subtenant shall not be
entitled to any interest payment on the Security Deposit.

  4.   Use of Subleased Premises.  (a) Subtenant shall use the Subleased
Premises for general office purposes or as otherwise permitted by the Base
Lease.

  (b)  Subtenant shall be conclusively deemed to have accepted the Subleased
Premises in the condition existing on the date Subtenant first takes possession
thereof and to have waived all claims relating to the condition of the Subleased
Premises. No agreement of Sublandlord to alter, remodel, decorate, clean or
improve the Subleased Premises or the Building and no representation regarding
the condition of the Subleased Premises has been made by or on behalf of
Sublandlord to Subtenant, except as specifically stated in this Sublease.
Notwithstanding the foregoing to the contrary, as of the end of the term hereof
and provided Subtenant is not in default hereunder beyond applicable cure
periods, Sublandlord shall assign and transfer to Subtenant, as if by bill of
sale, all furniture located in the Subleased Premises as of the date of this
Sublease, together with the racks, wiring and audio visual equipment located in
the phone room in the Subleased Premises, provided Subtenant shall have the use
of said furniture during the term hereof if Subtenant is not in default
hereunder beyond applicable cure periods. Subtenant shall accept the foregoing
in an "as is", "where is" physical condition, without any representation or
warranty on the part of Sublandlord, except for Sublandlord's representation of
its ownership of the same. The
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maintenance and repair obligations set forth in paragraph 5 below shall apply to
the foregoing furniture and equipment.

  (c)  Subtenant shall make arrangements directly with the telephone company for
telephone service to the Subleased Premises. Subtenant shall promptly pay and be
solely responsible for the entire cost of all such service. Subtenant shall also
pay upon Sublandlord's demand the reasonable cost of removing any special
equipment installed by Subtenant in the Subleased Premises upon expiration of
the term of the Sublease or the termination of this Sublease, provided no such
removal shall be required if the term hereof shall end on November 14, 1999, and
such removal is not required pursuant to the terms of the Base Lease. Subtenant
shall make all necessary arrangements with the utility company serving the
Building for electricity to be used in the Subleased Premises, and Subtenant
shall pay all charges with respect thereto before the same shall be due.
Subtenant shall make no alterations or additions to the wiring installation,
electric equipment or appliances without the prior written consent of
Sublandlord in each instance. Subtenant acknowledges that the electrical feeder
or riser capacity serving the Subleased Premises on the Commencement Date is
adequate to serve its use of the same. Subtenant covenants and agrees that at
all times its use of electric current shall never exceed the capacity of the
feeders to the Building or the risers or wiring installation.

  (d)  Subtenant shall be entitled to possession of the Subleased Premises upon
the Commencement Date. In the event of the failure of Sublandlord to deliver
possession of the Subleased Premises upon the Commencement Date, neither
Sublandlord nor its agents shall be liable for any damages caused thereby, nor
shall this Sublease thereby become void or voidable, nor shall the term of this
Sublease be in any way extended but in such event said term shall begin when
Sublandlord does deliver possession of the Subleased Premises, and the Subtenant
shall not be liable for any monthly gross rent until the time that Sublandlord
delivers such possession. Notwithstanding anything contained herein to the
contrary, Subtenant may terminate this Sublease in the event the Commencement
Date shall not occur by August 1, 1998, provided Subtenant must deliver notice
of such termination to Sublandlord on or before the fifth (5th) day following
said date.

  5.   Maintenance and Repairs.  (a) Subtenant shall, at Subtenant's
sole cost and expense and to the extent required of the tenant under the Base
Lease, keep the Subleased Premises in good repair and condition, and shall
perform all obligations of Sublandlord under the Base Lease with respect
thereto.

  (b)  Upon the termination of this Sublease, Subtenant shall deliver possession
of the Subleased Premises to Sublandlord in good order, condition and repair,
and otherwise as required by, and subject to, the provisions of the Base Lease.

  (c)  Subtenant shall not, without the prior written consent of Sublandlord, 
make or cause to be made any alterations, improvements, additions, installations
or decorations in or to the Subleased Premises. Sublandlord may require as a
condition
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of granting such consent that, before commencement of any such work or delivery
of any materials into the Subleased Premises or the Building, Subtenant shall
furnish to Sublandlord and Landlord for approval architectural plans and
specifications, names and addresses of all contractors, contracts, necessary
permits and licenses, certificates of insurance and instruments of
indemnification against any and all claims, costs, expenses, damages and
liabilities which may arise in connection with such work, all in such form and
amount as may be reasonably satisfactory to Sublandlord and Landlord. Subtenant
agrees to hold Sublandlord, Landlord and their respective agents and employees
forever harmless against all claims and liabilities of every kind, nature and
description which may arise out of or in any way be connected with such work.
All such work shall be done only by contractors or mechanics reasonably approved
by Sublandlord and Landlord (which approval may be withheld in Sublandlord's and
Landlord's reasonable discretion) and at such time and in such manner as
Sublandlord and Landlord may from time to time reasonably designate. Subtenant
shall pay the cost of all such work and the cost of decorating the Subleased
Premises and the Building occasioned thereby. Upon completion of such work,
Subtenant shall furnish Sublandlord with contractor's affidavits and full and
final waivers of lien and receipted bills covering all labor and materials
expended and used in connection therewith. All such work shall be in accordance
with the Base Lease, applicable legal, governmental and quasi-governmental
requirements, ordinances and rules (including the Board of Fire Underwriters),
and all requirements of applicable insurance companies. All such work shall be
done in a good and workmanlike manner, with the use of good grades of materials
and in conformity with so-called building standards. Sublandlord and Landlord
may, at their option supervise, at Subtenant's cost (as provided in the Base
Lease) construction operations in connection with such work; provided, however,
that such supervision or right to supervise by Sublandlord shall not constitute
any warranty by Sublandlord to Subtenant of the adequacy of the design,
workmanship or quality of such work or materials for Subtenant's intended use or
impose any liability upon Sublandlord or Landlord in connection with the
performance of such work. All alterations, improvements, additions and
installations to or on the Subleased Premises shall become part of the Subleased
Premises at the time of their installation and, at the election of Sublandlord
or Landlord, shall remain in the Subleased Premises at the expiration or
termination of this Sublease, or termination of Subtenant's right of possession
of the Subleased Premises, without compensation or credit to Subtenant.
Subtenant shall not pledge, mortgage, hypothecate or in any way create a
security interest in and to any of the alterations and improvements provided for
herein to any creditor or third party without the prior written consent of
Sublandlord and Landlord.

  6.   Assignment.  Subtenant shall not sublease, assign, mortgage,
pledge, hypothecate or otherwise transfer or permit the transfer of this
Sublease or the interest of Subtenant in this Sublease, in whole or in part, by
operation of law or otherwise.

  7.   Concerning the Base Lease.  (a)  It is understood and agreed that
the interest of Sublandlord hereunder and in the Subleased Premises hereby
demised is solely as tenant under the Base Lease, and that this Sublease and
Subtenant's rights and Sublandlord's obligations hereunder are subject to and
subordinate to the Base 
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Lease, including the termination provisions thereof.

  (b)  There are hereby reserved unto Sublandlord all rights reserved to the
Landlord under the Base Lease.

  (c)  Sublandlord shall have the benefit of all covenants and undertakings of 
the Landlord under the Base Lease insofar as they apply to the Subleased
Premises, including the right to enforce such covenants and undertakings, by
litigation or otherwise, but the sole obligation of Sublandlord hereunder with
respect thereto shall be to give notice to the Landlord under the Base Lease of
any non-performance thereof when Sublandlord hereunder shall receive written
notice thereof from Subtenant hereunder, and to demand performance of same.
Subtenant shall promptly deliver to Sublandlord copies of all notices received
by Subtenant from Landlord with reference to the Subleased Premises. In the
event of a default by Landlord under the Base Lease which adversely affects
Subtenant's rights under this Sublease and/or its use and occupancy of the
Subleased Premises, then Subtenant may upon Sublandlord's consent (which consent
shall not be unreasonably withheld) pursue legal remedies against Landlord under
the Base Lease, at Subtenant's sole cost and expense, and Sublandlord hereby
consents to Subtenant's pursuit of such remedy and assigns to Subtenant its
rights to pursue same.

  (d)  As to the Subleased Premises, Subtenant hereby covenants and agrees to be
bound by and to perform every term, provision, covenant and condition, expressed
or implied, imposed upon Sublandlord by the Base Lease, except as otherwise
expressly provided herein or with reference to rentals which are to be paid
directly by Subtenant to Sublandlord, and except as otherwise expressly provided
pursuant to the other provisions of this Sublease, provided the same are more
restrictive than the applicable provisions in the Base Lease. All such
obligations so assumed by Subtenant hereunder shall be for the benefit of, and
shall be enforceable by, Sublandlord or Landlord or both. Subtenant agrees not
to take any action in violation of the terms and conditions of the Base Lease,
and Subtenant hereby agrees to indemnify, defend and hold Sublandlord harmless
from and against any and all claims, expenses, damages and liabilities
(including attorneys' fees and costs) to which Sublandlord may be subject by
reason of Subtenant's failure to comply with any of the terms and conditions of
the Base Lease, as to the Subleased Premises. Sublandlord agrees not to take any
action in violation of the terms and conditions of the Base Lease.

  (e)  Notwithstanding anything to the contrary in this Sublease, all of the
Subtenant's rights hereunder shall be subject to prior or subsequent termination
of the Base Lease, pursuant to any provisions thereof, or otherwise.

  (f)  Sublandlord agrees not to enter into any amendment, modification,
supplement or other termination agreement which will materially adversely
increase Subtenant's obligations or materially adversely decrease Subtenant's
rights under this Sublease or the Base Lease. Sublandlord represents and
warrants that it is not in default (beyond applicable cure periods) of its
obligations under the Base Lease.
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Further, Sublandlord agrees to perform its obligations under the Base Lease so
as to avoid a default (beyond applicable cure periods) thereunder. Sublandlord
shall not do anything or suffer or knowingly permit anything to be done which
results in a default (beyond applicable cure periods) under the Base Lease or
permit the Base to be cancelled or terminated.

  In the event Sublandlord shall default in the performance of any monetary
obligations under the Base Lease which will have a material adverse affect upon
Subtenant, and Sublandlord shall fail to cure said default within thirty (30)
days following written notice from Subtenant with respect thereto, Subtenant
shall be permitted to cure such default by tendering performance directly to
Landlord and Sublandlord shall pay to Subtenant all costs and expenses incurred
by Subtenant with respect to the same, provided Subtenant is not in default
hereunder.

  8.   Indemnity, Exoneration.  (a)  Subtenant shall defend, hold
harmless and indemnify Sublandlord at all times against any loss, damage, costs
or expenses by reason of any accident, injury (including death), loss or damage
occurring on or about the Subleased Premises or resulting from any act or thing
done or omitted to be done on or about the Subleased Premises by Subtenant or
Subtenant's agents, employees, invitees and/or contractors.

  (b)  Except with respect to the negligence of Sublandlord or its agents,
contractors or employees, neither Sublandlord, nor its agents, partners,
employees or contractors shall be liable for any accident, injury (including
death), loss or damage resulting to any person or property sustained by
Subtenant or Subtenant's agents, employees, contractors or invitees, or any
occupant of the Building or anyone claiming by or through them and resulting
from any defect in the Building or the Subleased Premises, or in any equipment
or appurtenance in the same, or resulting from any accident or occurrence in or
about the Building or the Subleased Premises, or resulting directly or
indirectly from any acts of negligence of any tenant or other occupant of
Building, or of any person or entity whatsoever. All property of Subtenant or
Subtenant's agents, employees, contractors and invitees, or of any occupant or
user of the Subleased Premises shall be at the risk of Subtenant or such other
person or entity only, and Sublandlord shall not be liable for any damage
thereto except with respect to the negligence of Sublandlord or its agents,
contractors or employees.

  9.   Default by Subtenant.  In the event of the breach by Subtenant of any of
the terms, provisions, covenants, conditions or agreements of this Sublease
Agreement, or of the Base Lease, Sublandlord shall have all the rights of the
Landlord under the Base Lease and Subtenant shall be subject to all provisions
thereof respecting the Tenant under the Base Lease.

  10. Notices. All notices required or permitted to be given hereunder shall be
in writing and shall be deemed given and delivered, whether or not received,
when personally delivered by the other party or its designated agent or courier
service, or, if sent by mail, when deposited in the United States Mail, postage
prepaid and properly
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                                                                          Page 7

addressed, certified mail, return receipt requested, at the following addresses:
(i) To Sublandlord: Ann Hasse, Esq., APL Land Transport Services, Inc., 1111
Broadway, Oakland, California 94607 and to Paul R. Diamond, Holleb & Coff, 55
East Monroe Street, Suite 3900, Chicago, Illinois 60603 or such other addresses
as Sublandlord shall designate by written notice to Subtenant; and (ii) To
Subtenant: at the address of the Subleased Premises and at 1815 S. Meyers Road,
Oak Brook Terrace, Illinois 60181, Attention: Legal Department, or such other
address as Subtenant shall designate by written notice to Sublandlord.

  11.  Condition Precedent.  This Sublease, and the rights and obligations of 
all parties hereto, are subject to the condition precedent of the consent of
such Landlord to the making of this Sublease Agreement.

  12.  Holding Over.  In the event Subtenant shall retain possession of the
Subleased Premises, or any portion thereof, after the expiration or termination
of this Sublease, Subtenant shall defend, indemnify and hold harmless Sublessor
with respect to any holdover claims made by the Landlord under the Base Lease
and any costs incurred by Sublandlord with respect thereto.

  13.  Real Estate Brokers.  Subtenant and Sublandlord represent that they have
not dealt with any real estate brokers, sales persons, or finders in connection
with this Sublease other than Trammell Crow Company and LaSalle Partners and no
other persons initiated or participated in the negotiation of this Sublease, or
showed the Subleased Premises to Subtenant. Any party breaching said
representation shall indemnify, defend and hold harmless the nonbreaching party
from and against any and all liabilities and claims for commissions and fees
arising out of a breach of the foregoing representation.

  14.  Late Charges.  Notwithstanding anything contained in the Base Lease to 
the contrary, all delinquent payments due from Subtenant to Sublandlord (i)
shall bear interest at twelve percent (12%) per annum or the maximum rate
permitted by law, and (ii) Subtenant shall pay a flat late charge of five
percent (5%) of the delinquent rent.

  15.  Sublandlord's Right to Perform Subtenant's Duties.  Notwithstanding
anything contained in the Base Lease, if Subtenant fails to timely perform any
of its duties under this Sublease, Sublandlord shall have the right (but not the
obligation), to perform such duty on behalf and at the expense of Subtenant
without further prior notice to Subtenant, and all sums expended or expenses
incurred by Sublandlord in performing such duty shall be deemed to be rent under
this Sublease and shall be due and payable upon demand by Sublandlord, together
with an administration charge of fifteen percent (15%) of the amounts so
expended.

  16.  Recording.  Neither Sublandlord nor Subtenant shall record this
Sublease; provided, however if Sublandlord requests, the parties shall execute
and acknowledge a short form of sublease for recording purposes which shall be
recorded at Sublandlord's expense.
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  17.  Joint Effort.  The preparation of this Sublease has been a joint
effort of the parties hereto and the resulting document shall not, solely as a
matter of judicial construction, be construed more severely against one of the
parties than the other.

  18.  Rights of Sublandlord.  Notwithstanding anything in this Sublease to the
contrary, in no event shall Subtenant be obligated to pay sums coming due and
payable under the Base Lease or otherwise. Sublandlord agrees that it will pay
all sums due and payable under the Base Lease as and when the same become due
and payable. Sublandlord represents and warrants to Subtenant that neither
Landlord nor Sublandlord is in default under the Prime Lease nor any other
agreement relating to the Sublease Premises, that no event has occurred which,
with the passage of time or the giving of notice or both, would constitute such
a default. In addition, Sublandlord further represents and warrants to Subtenant
that neither Sublandlord nor any agent or affiliate of Sublandlord nor any agent
of Sublandlord has received any notice of zoning, building, fire, health,
safety, environmental or other violations of law which have not heretofore been
entirely corrected. Notwithstanding anything to the contrary contained in this
Sublease, Subtenant may, without the consent of Sublandlord and without
application of any right of recapture, assign its interest in the Sublease or
sublet a portion of the premises to an "affiliate" of Subtenant, provided
Subtenant is permitted to do so and complies with the terms of the Base Lease.
For purposes of this Sublease, an "affiliate" of Subtenant shall mean any entity
which (i) owns all or a majority of the ownership interest of Subtenant either
directly or indirectly through other subsidiaries or is owned or controlled by
the same person or entity which owns Subtenant or which controls Subtenant, or
(ii) which results from a merger or consolidation with Subtenant. Additionally,
this Sublease shall contain no provision restricting in any manner a change of
control or a change in shareholders, directors, management or organization of
Subtenant or any subsidiary or affiliate of Subtenant or any parent or to the
issuance, sale, purchase or disposition of shares of Subtenant or any subsidiary
or affiliate of Subtenant, provided, however, nothing contained herein shall be
construed to limit Landlord's rights under the Base Lease.

  19.  Calculation of Time.  Unless specifically stated otherwise, any
reference herein to a specific period of days shall be interpreted as a
reference to calendar days; provided, however, that if such period would
otherwise end on a Saturday, Sunday or generally recognized holiday, then the
period shall be deemed to end on the following day.

  20.  Partial Invalidity.  If any term, covenant or condition of this
Sublease or the application thereof to any person or circumstance shall, to any
extent, be invalid or unenforceable, the remainder of this Sublease or the
application of such term, covenant or condition to persons or circumstances
other than those as to which it is held invalid or unenforceable shall not be
affected thereby and each term, covenant or condition of this Sublease shall be
valid and be enforced to the fullest extent permitted by law.

  IN WITNESS WHEREOF, the parties hereto have executed this Sublease 
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Agreement the day and year first above written.

Sublandlord:                          Subtenant:

APL LAND TRANSPORT SERVICES, INC.       PLATINUM TECHNOLOGY, INC.

By:  Michael Gedney                           By:   R. W. Powell
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Its: M.D. Central Region                      Its:  V.P. Real Estate         
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