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                                                                  EXHIBIT 10.23


                               SUBLEASE AGREEMENT


1.    PARTIES.
      This Sublease, dated May 23, 1996, is made between CTA Incorporated (CTA)
      ("Sublessor") and Manugistics, Inc. (Manugistics) ("Sublessee").

2.    MASTER LEASE.
      Sublessor is the lessee under a written lease dated February 6, 1989,
      wherein 6116 Limited Partnership ("Lessor") leased to Sublessor the real
      property located at 6116 Executive Boulevard, Rockville, Maryland,
      described as approximately 49,451 square feet located on the third (3rd)
      and eighth (8th) floors ("Master Premises").

3.    PREMISES.
      Sublessor hereby subleases to Sublessee on the terms and conditions set
      forth in this Sublease the following portion of the Master Premises
      ("Premises"): Approximately 20,639 square feet on the third (3rd) floor.
      See attached copy of floor plan marked as Exhibit A.

4.    WARRANTY BY SUBLESSOR.
      Sublessor warrants and represents to Sublessee that the Master Lease has
      not been amended or modified except as expressly set forth herein, that
      Sublessor is not now, and as of the commencement of the Term hereof will
      not be, in default of breach of any of the provisions of the Master Lease,
      and that Sublessor has no knowledge of any claim by Lessor that Sublessor
      is in default or breach of the provisions of the Master Lease. In the
      event that Sublessor is ever placed in default of the Master Lease, the
      Sublessor shall have the right to cure such default. In the event
      Sublessor does not cure such default within the time allowed by the Master
      Lease, the Sublessee shall have the right to immediately cancel the
      Sublease.

5.    TERM.
      The Term of this Sublease shall commence 120 days from the date of this
      agreement ("Commencement Date"), and end on June 30, 1999 ("Termination
      Date"), unless otherwise sooner terminated in accordance with the
      provisions of this Sublease. Possession of the Premises ("Possession")
      shall be delivered to Sublessee 60 days from the date of this agreement,
      for the sole purpose of retrofitting the Premises.

6.    RENT.
      Sublessee shall pay to Sublessor as base rent, without deduction, setoff,
      notice, or demand, at 6116 Executive Boulevard, Rockville, Maryland, or at
      such other place as Sublessor shall designate from time to time by notice
      to Sublessee, the annual sum of Three Hundred Seventy-One Thousand Five
      Hundred Two and 00/100 Dollars, ($371,502.00), paid in equal monthly
      installments of Thirty Thousand Nine Hundred Fifty-Eight and 50/100
      Dollars ($30,958.50), in advance on the first

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      day of each month of the Term. If the term begins or ends on a day other
      than the first or last day of a month, the rent for the partial months
      shall be prorated on a per diem basis. At the commencement of each lease
      year, the base rent shall be increased by three and one-quarter percent
      (3.25%).

7.    USE OF PREMISES.
      The Premises shall be used and occupied only for general office use and
      for no other use or purpose.

8.    ASSIGNMENT AND SUBLETTING.
      Sublessee shall not assign this Sublease or further sublet all or any part
      of the Premises except to a party controlling, controlled by, or under
      common control with Sublessee without the prior written consent of
      Sublessor, which shall not be unreasonably withheld, conditioned or
      delayed, (and the consent of Lessor, if such is required under the terms
      of the Master Lease).

9.    OTHER PROVISIONS OF THE SUBLEASE.
      AB applicable terms and conditions of the Master Lease are incorporated
      into and made a part of this Sublease as if Sublessor were the lessor
      thereunder, Sublessee the lessee thereunder and the Premises the Master
      Premises. The following articles do not apply to the Sublease, including,
      but not limited to: Article 6 and Addendum No. 1, Article 3, Article 4,
      Article 7, Article 8, Article 9, Article 10, Article 11, Article 13,
      Article 14, and Article 19 (b), (c) and (d). Sublessee assumes and agrees
      to perform the lessee's obligations under the Master Lease during the Term
      to the extent that such obligations are applicable to the Premises, except
      that the obligation to pay rent to Lessor under the Master Lease shall be
      considered performed by Sublessee to the extent and in the amount rent is
      paid to Sublessor in accordance with Section 6 of this Sublease. Sublessee
      shall not commit or suffer any act or omission that will violate any of
      the provisions of the Master Lease. Sublessor shall exercise due diligence
      in attempting to cause Lessor to perform its obligations under the Master
      Lease for the benefit of Sublessee. If the Master Lease terminates, this
      Sublease shall terminate and the parties shall be relieved of any further
      liability or obligation under this Sublease, provided however, that if the
      Master Lease terminates as a result of a default or breach by Sublessor or
      Sublessee under this Sublease and/or the Master Lease, then the defaulting
      party shall be liable to the nondefaulting party for the damage suffered
      as a result of such termination. Notwithstanding the foregoing, if the
      Master Lease gives Sublessor any right to terminate the Master Lease in
      the event of the partial or total damage, destruction, or condemnation of
      the Master Premises of the building or project of which the Master
      Premises are a part, the exercise of such right by Sublessor shall not
      constitute a default or breach hereunder. In the event that Sublessee
      abandons the premises while maintaining rent payments to Sublessor,
      Sublessee shall not be considered in default of the Sublease.





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10.   ATTORNEY'S FEES.
      If Sublessor or Sublessee shall commence an action against the other
      arising out of or in connection with this Sublease, the prevailing party
      shall be entitled to recover its cost of suit and reasonable attorney's
      fees.

11.   LIMITATION OF LIABILITY.
      Neither party shall be liable for loss of profit, goodwill or other
      consequential damage arising out of this agreement even if advised of the
      possibility of such damages. Either party's liability for all claims
      (excluding physical injury or property damage resulting from negligent or
      willful misconduct) that arise out of this agreement shall not exceed the
      sum of rent paid by the Sublessee to the Sublessor for the year in which
      the cause of action arose.

12.   HOLDOVER.
      Sublessee shall have no rights to occupy the premises beyond the
      Termination Date of June 30, 1999 stated in this Sublease Agreement. In
      the event the Sublessee continues to occupy the premises beyond the
      Termination Date, this action shall constitute a Holdover by the
      Sublessee. Sublessee hereby understands and agrees that in the event of a
      Holdover by the Sublessee, the Sublessee is bound by the terms of the
      Master Lease and shall be responsible for all damages, penalties, and
      costs resulting from such action. Sublessee further agrees that any and
      all damages, penalties, and costs resulting from a holdover by the
      Sublessee shall not be limited to the sum of rent paid by the Sublessee to
      the Sublessor for the year in which the action occurred.

13.   NOTICES.
      All notices and demands which may or are to be required or permitted to be
      given by either party on the other hereunder shall be in writing. All
      notices and demands by the Sublessor to Sublessee shall be sent by United
      States Mail, postage prepaid, addressed to the Sublessee at the Premises,
      and to the address herein below, or to such other place as Sublessee may
      from time to time designate in a notice to the Sublessor. All notices and
      demands by the Sublessee to Sublessor shall be sent by United States Mail,
      postage prepaid, addressed to the Sublessor at the address set forth
      herein, and to such other person or place as the Sublessor may from time
      to time designate in a notice to the Sublessee.

      To Sublessor:       CTA Incorporated
                          6116 Executive Boulevard
                          Rockville, Maryland

      To Sublessee:       Manugistics, Inc.
                          Attention: General Counsel
                          2115 East Jefferson Street
                          Rockville, Maryland 20852




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14.   CONSENT BY LESSOR.
      This Sublease shall be of no force or effect unless consented to by the
      Lessor after execution thereof, if such consent is required under the
      terms of the Master Lease.

15.   CONDITION OF THE PREMISES.
      Sublessee accepts the Demised Premises in their present "as is" condition
      and configuration. Sublessor shall be responsible for demising the space.

16.   PARKING.
      Sublessor shall provide sixty-four (64) parking spaces for Sublessee's use
      at no charge at the commencement of the Sublease and for the entire term.

17.   AFTER HOURS HVAC.
      Sublessee shall be responsible for overtime HVAC charges applied to the
      Sublessor as may be provided for in the Master Lease

18.   GENERAL.

      A.   GOVERNING LAW.  Sublease shall be construed and enforced in
           accordance with the laws of the state of Maryland.

      B.   SEVERABILITY.  Any provision of this Sublease that is held to be
           invalid by a court of competent jurisdiction shall be severed from
           this Sublease, and the remaining provisions shall remain in full
           force and effect.

      C.   FORCE MAJEURE.  Neither party shall be liable to the other party for
           failure or delay in fulfilling its obligations under this Sublease to
           the extent that such failure or delay is due to causes beyond its
           control, including, but not limited to: acts of God; war, civil
           disturbance; and riot.

      D.   WAIVER.  Failure or delay by either party to enforce compliance with
           any term or condition of this Sublease shall not constitute a waiver
           of such term or condition.

      E.   ENTIRE AGREEMENT. This Sublease shall constitute the entire agreement
           between the parties with regard to the subject matter of this
           Sublease and supersede all previous communications, whether oral or
           written, between the parties with respect to such subject matter.
           Neither the course of conduct between the parties nor trade usage
           shall modify or alter this Sublease. If either party issues a
           purchase order or other writing addressing the subject matter of this
           Sublease, such purchase order or writing shall be for issuing party's
           internal purposes only, and the terms and conditions contained
           therein shall have no force or effect.

      F.   MODIFICATION.  No waiver or modification of any of the provisions
           hereof shall be binding unless in writing and signed by duly
           authorized representatives of both parties.



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      The parties hereto have executed this sublease agreement.



/s/ GREGORY H. WAGNER                          Date:  May 23, 1996
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SUBLESSOR: CTA Incorporated

By:

/s/ HELEN NATASIA                              Date:  May 15, 1996
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SUBLESSEE:   Manugistics, Inc.
             Helen Natasia

By:          GENERAL COUNSEL






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