Exhibit 10.13

                   URS CORPORATION 1991 STOCK INCENTIVE PLAN:

                   CONTINGENT RESTRICTED STOCK AWARD AGREEMENT



URS  Corporation,  a Delaware  corporation  ("URS"),  hereby  promises  to award
Restricted  Shares of its common stock to the recipient  named below.  The terms
and conditions of such  contingent  award are set forth in this cover sheet,  in
the attachment and in the URS Corporation  1991 Stock Incentive Plan, as amended
(the "Plan").

Date of Contingent Award:                                     December 16, 1997

Name of Recipient:                                            Kent P. Ainsworth

Recipient's Social Security Number:                           

Number of Shares of URS Common Stock
Covered by Contingent Award:                                  25,000

Performance Period Commencement Date:                         December 16, 1997





             By signing this cover sheet, you agree to all the terms
           and conditions described in the attachment and in the Plan.



Recipient:                          /s/ Kent P. Ainsworth             
                                    --------------------------------------------
                                             KENT P. AINSWORTH



URS Corporation:                    By: /s/Joseph Masters                   
                                    --------------------------------------------
                                           JOSEPH MASTERS
                                           Vice President and General Counsel


Attachment

                                       1.



                   URS CORPORATION 1991 STOCK INCENTIVE PLAN:

                   CONTINGENT RESTRICTED STOCK AWARD AGREEMENT



Payment for Shares

Due to legal  requirements,  you must pay to URS the par value of any shares you
receive  pursuant  to this  contingent  award.  The  amount is $0.01 per  share,
payable by check.

Contingent Award of Shares

You are hereby  contingently  granted up to 25,000  Restricted  Shares under the
Plan (the  "Maximum  Number of  Shares"),  the exact  number to be granted to be
determined based on the cumulative  annualized total returns to URS stockholders
("Total  Returns") over the five-year period beginning on December 16, 1997 (the
"Commencement  Date") and ending on  December  16, 2002 (such  five-year  period
being hereafter  referred to as the  "Performance  Period").  No shares shall be
granted if Total  Returns  are 8.0% or less,  and 100% of such  shares  shall be
granted if Total  Returns are 12.0% or more. If Total Returns are more than 8.0%
but less than 12.0%,  the number of shares  granted shall be that  percentage of
the  Maximum  Number of Shares  determined  on a  straight-line  prorated  basis
between 8.0% and 12.0%.

Up to  one-third  of the  Maximum  Number of Shares  shall be granted  effective
December  16, 2000 based on Total  Returns  from the  Commencement  Date to such
date;  up to  two-thirds  of the  Maximum  Number  of  Shares  shall be  granted
effective December 16, 2001 based on Total Returns from the Commencement Date to
such date,  and up to the Maximum  Number of Shares  shall be granted  effective
December 16, 2002 based on Total Returns for the entire Performance Period. Once
granted,  the shares will be fully vested and will not be subject to retroactive
adjustment even if Total Returns calculated as of a subsequent date are less.

Calculation of Total Returns

Total Returns shall be  calculated  on the basis of the  difference  between the
closing  price of a share of URS Common Stock on the New York Stock  Exchange on
the  Commencement  Date,  which is agreed to be $14.0625 per share, and the Fair
Market  Value (as defined  below) of a share of URS Common Stock (as adjusted on
December  16, 2000,  2001 and 2002,  respectively,  or the next  business day on
which such exchange is opened for trading if such day is not a trading day (each
a "Calculation  Date"). Such difference shall be converted into an annual return
on an annualized compound basis, with the resulting number being "Total Returns"
for purposes of this Agreement.

"Fair Market Value" shall be equal to the closing price of a share of URS Common
Stock (as adjusted below) on the New York Stock Exchange on a Calculation  Date.
If for any reason URS Common Stock is not traded on the New York Stock  Exchange
on any such date,  then Fair  Market  Value  shall be the  closing  price on the
principal  exchange on which the URS Common Stock is then traded, or as reported
through the principal automated quotation system if URS Common Stock is not then
traded on an exchange, or as determined in good faith by the 


                                       1.


Compensation/Option Committee of the URS Board of Directors (the "Committee") in
the event that URS Common  Stock is not then  either  traded on an  exchange  or
reported through an automated quotation system.

In the event that at any time between the  Commencement  Date and a  Calculation
Date a dividend or other distribution is declared on shares of URS Common Stock,
then such dividend or other  distribution  shall  immediately  be deemed to have
been reinvested in additional shares of URS Common Stock at its then Fair Market
Value,  and the number of shares of URS Common Stock for purposes of determining
Total Returns as of a Calculation  Date shall be adjusted  accordingly.  If such
dividend  or other  distribution  is in a form other  than  cash,  then its cash
equivalent  for purposes of determining  the amount of such deemed  reinvestment
shall be determined in good faith by the Committee.

In the event that shares of URS Common Stock are converted into or exchanged for
different securities through a merger, reorganization, recapitalization or other
similar transaction,  then Total Returns shall be calculated on the basis of the
difference  between the closing  price of a share of URS Common Stock on the New
York Stock  Exchange on the  Commencement  Date and the Fair Market Value of the
securities  into  which a share  of URS  Common  Stock  has  been  converted  or
exchanged  following  the  above  principles,   as  applied  to  the  particular
circumstances in good faith by the Committee.


The following table  summarizes the possible grants of Shares,  assuming various
Total Returns over the Performance Period:


             Total Returns                     Restricted Shares Awarded                Projected Stock Price
                                                                                               
                12.0%                                        25,000                             $24.7829
                11.0%                                        18,750                             $23.6961
                10.0%                                        12,500                             $22.6478
                 9.0%                                         6,250                             $21.6369
                 8.0%                                             0                             $20.6624



For purposes of calculating Total Returns,  all numbers shall be rounded down to
the nearest one tenth of one percent (e.g., 11.94% is rounded down to 11.9%).

Granted Shares Not Restricted

Shares  granted under the foregoing  provisions  will be considered  "Restricted
Shares"  under the Plan that have  vested in full on the date of grant.  You may
sell,  transfer,  pledge or  otherwise  dispose of any such  Restricted  Shares.
However, see "Restrictions on Resale" below.

Accelerated Grant and Forfeiture

                                       2.


If at any time during the  Performance  Period URS terminates your service as an
employee  for any reason  other then Cause (as defined  below) or you  terminate
your service as an employee of URS for Good Reason (as defined below),  then any
shares not previously granted to you under the terms of this Agreement as of the
date of  termination,  up to the Maximum Number of Shares,  shall be immediately
granted.

If at any time during the  Performance  Period URS terminates your service as an
employee for "Cause",  then any shares not  previously  granted to you under the
terms of this  Agreement  as of the date of  termination  shall  immediately  be
forfeited.

For purposes of this  Agreement,  "Cause" and "Good  Reason" shall have the same
meanings  assigned to such terms in your Employment  Agreement with URS dated as
of May 7, 1991, as the same may be amended from time-to-time.

Leaves of Absence

For purposes of this contingent  award, your service does not terminate when you
go on a military  leave, a sick leave or another bona fide leave of absence,  if
the leave was approved by URS in writing.  But your service  terminates when the
approved leave ends, unless you immediately return to active work.

Stock Certificates

After a grant of Restricted Shares based on this contingent award has been made,
a stock  certificate  for those shares will be issued to you (or to you and your
spouse).

Voting Rights

You may vote only those shares that have been granted to you.

Withholding Taxes

No stock  certificates  will be issued to you  unless  you have made  acceptable
arrangements to pay any withholding  taxes that may be due as a result of grants
of shares pursuant to this contingent award.

Restrictions on Resale

By  signing  this  Agreement,  you agree  not to sell any  shares at a time when
applicable  securities  or  other  laws or US  policies  prohibit  a sale.  This
restriction will apply as long as you are an employee,  director,  consultant or
advisor of URS (or any subsidiary).

Retention Rights

Neither your award nor this Agreement  gives you the right to be retained by URS
(or any subsidiaries) in any capacity.  URS (and any  subsidiaries)  reserve the
right to terminate your service at any time, with or without cause.

                                       3.


Adjustments

In the event of a stock  split,  a stock  dividend  or a  similar  change in URS
stock, the number of Restricted Shares that are subject to this contingent award
will be adjusted accordingly.

Applicable Law

This Agreement  will be interpreted  and enforced under the laws of the State of
California.

The Plan and Other Agreements

The text of the 1991 Stock  Incentive Plan is  incorporated in this Agreement by
reference.

This Agreement and the Plan constitute the entire understanding  between you and
URS regarding this award.  Any prior  agreements,  commitments  or  negotiations
concerning this award are superseded.

                  By signing the cover sheet of this Agreement,
                    you agree to all the terms and conditions
                        described above and in the Plan.




                                       4.