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                                                                  Exhibit 10.1

                                                    Tenant Extension Amendment

                              SECOND AMENDMENT

     This Second Amendment (the "Amendment") is made and entered into as of
the 24 day of March, 1997, by and between ZML-ONE MARKET LIMITED PARTNERSHIP,
a Delaware limited partnership ("Landlord") by its agent, Equity Office
Holdings, LLC, a Delaware limited liability company, and TENERA, INC., a
Delaware corporation ("Tenant").

                                 WITNESSETH

A.   WHEREAS, Landlord and Tenant are parties to that certain lease dated
August 2, 1995, currently containing approximately 13,496 rentable square feet
of space described as Suite No. 1850 on the eighteenth floor of the building
commonly known as Spear Tower and the address of which is One Market, San
Francisco, CA (the "Building"), which Lease has been previously amended by the
First Amendment dated March 28, 1996 (collectively, the "Lease"); and

B.   WHEREAS, the Lease by its terms shall expire on October 31, 1997 ("Prior
Termination Date"), and the parties desire to extend the Lease, all on the
terms and conditions hereinafter set forth;

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

     I.    Extension.  The Lease Term is hereby extended from two years and
two months to five years and two months and the Termination Date is
accordingly amended from the Prior Termination Date to October 31, 2000
("Extended Termination Date"), unless sooner terminated in accordance with the
terms of the Lease.  That portion of the Lease Term commencing the day
immediately following the Prior Termination Date ("Extension Date") and ending
on the Extended Termination Date shall be referred to herein as the "Extended
Term".  In any and all events, the schedule of monthly installments of Base
Rental contained in Paragraph 11 of this Amendment shall not be postponed or
delayed if any improvements to the Premises are incomplete on the day
following the Prior Termination Date for any reason whatsoever.  Any delay in
the completion of improvements to the Premises, if any, or inconvenience
suffered by Tenant during the performance of any improvements shall not
subject Landlord to any liability for any loss or damage resulting therefrom
or entitle Tenant to any credit, abatement or adjustment of Rent.

     II.   Monthly Base Rental.  As of the date hereof, the schedule of
monthly installments of Base Rental contained in Exhibit B-1 to the Lease and
in Article 11 of the First Amendment is amended by adding the following as
applicable to the Extended Term:

     Tenant shall pay Landlord the sum of One Million One Hundred Seventy Four
Thousand One Hundred Fifty One and 88/100 Dollars ($1,174,151.88) as Base
Rental for the Extended Term in thirty six (36) monthly installments as
follows:

           A.  Thirty six (36) equal installments of $32,615.33 each payable
on or before the first day of each month during the period beginning November
1, 1997 and ending October 31, 2000.

           All such Base Rental shall be payable by Tenant in accordance with
the terms of Article V of the Lease.

     III.  Base Year. For the period commencing with the Extension Date and
ending on the Extended Termination Date, the Base Year for the computation of
Tenant's Pro Rata Share of Taxes and Expenses is amended from 1995 to 1997.

     IV.   Improvements to Premises.

           A.  Tenant is in possession of the Premises and accepts the same
"as is" without any agreements, representations, understandings or obligations
on the part of Landlord to perform any alterations, repairs or improvements,
except as may be expressly provided otherwise in this Amendment.

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           B.  Cost of Improvements to Premises.

               (i)  Provided Tenant is not in default, Tenant shall be
entitled to receive an improvement allowance (the "Extension Improvement
Allowance") in an amount not to exceed Thirteen Thousand Four Hundred Ninety
Six and no/100 Dollars ($13,496.00) to be applied toward the cost of
performing construction, alteration or improvement of the Premises, including
but not limited to the cost of space planning, design and related
architectural and engineering services.  In the event the total cost of the
improvements to the Premises exceeds the Extension Improvement Allowance,
Tenant shall pay for such excess upon demand.  The entire unused balance of
the Extension Improvement Allowance, if any, shall be applied as a credit
towards Base Rental for the Extended Term beginning with the Base Rental due
for January 1998 and continuing thereafter until the entire unused balance has
been applied.  Landlord shall pay such Extension Improvement Allowance
directly to the contractors retained to perform the construction, design or
related improvement work to the Premises.

           C.  Responsibility for Improvements to Premises.

               Work Performed By or On Behalf of Landlord Pursuant to Plans
Yet to Be Prepared.  Landlord shall enter into a direct contract for the
improvements to the Premises with a general contractor selected by Landlord.
Tenant shall devote such time in consultation with Landlord or Landlord's
architect as may be required to provide all information Landlord deems
necessary in order to enable Landlord to complete, and obtain Tenant's written
approval of, the plans for the improvements to the Premises in a timely
manner.  All plans for the improvements to the Premises shall be subject to
Landlord's consent, which consent shall not be unreasonably withheld.  If the
cost of such improvements exceeds the Extension Improvement Allowance, then
prior to commencing any construction of improvements to the Premises, Landlord
shall submit to Tenant a written estimate setting forth the anticipated cost,
including but not limited to the cost of space planning, design and related
architectural and engineering services, labor and materials, contractor's
fees, and permit fees.  Within a reasonable time thereafter, Tenant shall
either notify Landlord in writing of its approval of the cost estimate or
specify its objections thereto and any desired changes to the proposed
improvements.  In the event Tenant notifies Landlord of such objections and
desired changes, Tenant shall work with Landlord to reach a mutually
acceptable alternative cost estimate.

     V.    Other Pertinent Provisions. The Lease shall also be amended in that
Tenant acknowledges that all Landlord's obligations have been fulfilled
pursuant to Paragraph VIII.A of the First Amendment, Exhibit B of the First
Amendment, and Exhibit C of the Lease, and accordingly all those provisions
are null, void and of no further force and effect.  The parties further agree
that Exhibit E of the Lease is deleted in its entirety and is of no further
force and effect.

     VI.   Miscellaneous.

           A.  This Amendment sets forth the entire agreement between the
parties with respect to the matters set forth herein.  There have been no
additional oral or written representations or agreements.  Under no
circumstances shall Tenant be entitled to any Rent abatement, improvement
allowance, leasehold improvements, or other work to the Premises, or any
similar economic incentives that may have been provided Tenant in connection
with entering into the Lease, unless specifically set forth in this Amendment.

           B.  Except as herein modified or amended, the provisions,
conditions and terms of the Lease shall remain unchanged and in full force and
effect.

           C.  In the case of any inconsistency between the provisions of the
Lease and this Amendment, the provisions of this Amendment shall govern and
control.  Under no circumstances shall this Amendment be deemed to grant
Tenant any further right to extend the Lease; provided, however any additional
or further right to extend explicitly provided in the Lease is not hereby
deleted or waived.

           D.  Submission of this Amendment by Landlord is not an offer to
enter into this Amendment but rather is a solicitation for such an offer by
Tenant.  Landlord shall not be bound by this Amendment until Landlord has
executed and delivered the same to Tenant.

           E.  The capitalized terms used in this Amendment shall have the
same definitions as set forth in the Lease to the extent that such capitalized
terms are defined therein and not redefined in this Amendment.

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           F.  This Amendment shall be of no force and effect unless and until
accepted by any guarantors of the Lease, who by signing below shall agree that
their guarantee shall apply to the Lease as extended and otherwise amended
herein, unless such requirement is waived by Landlord in writing.

           G.  Tenant hereby represents to Landlord that Tenant has dealt with
no broker in connection with this Amendment.  Tenant agrees to indemnify and
hold Landlord and the Landlord Related Parties harmless from all claims of any
brokers claiming to have represented Tenant in connection with this Amendment.

     IN WITNESS WHEREOF, Landlord and Tenant have duly executed this Amendment
as of the day and year first above written.


WITNESSES; ATTESTATION           LANDLORD:  ZML-ONE MARKET LIMITED
                                 PARTNERSHIP, a Delaware limited partnership

                                 BY:  EQUITY OFFICE HOLDINGS, LLC, as Agent

                                 By:  /s/ PETER H. ADAMS
                                     -------------------------------------

                                 Name:  Peter H. Adams
/s/ ANDREW MCCONNELL                   -----------------------------------
-----------------------------
                                 Title:  Vice President
    Andrew McConnell                    ----------------------------------
-----------------------------

/s/ JAMES A. ROBISON, JR.        TENANT:  Tenera, Inc., a Delaware corporation
-----------------------------
                                 By:  /s/ JEFFREY R. HAZARIAN
    James A. Robison, Jr.            -------------------------------------
-----------------------------
                                 Its:  Chief Financial Officer
                                      ------------------------------------


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