FIRST AMENDMENT TO OPTION AGREEMENT

     THIS FIRST AMENDMENT TO OPTION AGREEMENT ("Amendment") is made and executed
as of this 22nd day of June, 1998 by and between
CONSTELLATION GATESPRING II, LLC ("Seller") and CORPORATE OFFICE
PROPERTIES, L.P., its successors and assigns ("Buyer").

     A.   Seller and Buyer entered into an Option Agreement dated May 14, 1988
pursuant to which Seller granted to Buyer the option to purchase the Property
known as Lot S-20 of the Columbia Gateway Business Park on which Seller intends
to develop and construct an office building containing approximately 100,000
gross square feet to be known as Woodlands Two (the "Option Agreement"). 
Capitalized terms used, but not defined, in this Amendment shall have the
meanings set forth in the Option Agreement.

     B.   By notice dated May 28, 1998, Buyer exercised its option to purchase
the Property.

     C.   Seller and Buyer desire to amend the Option Agreement as set forth in
this Amendment.

     NOW, THEREFORE, in consideration of the agreements contained herein and
intending to be legally bound hereby, Seller and Buyer agree as follows:

          1.   The first sentence of Section 1 of the Option Agreement is hereby
deleted, and the following sentence is substituted in its place:  "The Purchase
Price for the Property shall be determined as of the date of "Settlement"
(hereinafter defined) and shall be that sum which is equal to the "Seller's Book
Value" (hereinafter defined) of the Property, not to exceed $14,442,403.00 as
set forth on the attached Exhibit "Construction Budget" attached hereto assuming
that the building of 106,000 gross square feet to be constructed on the Property
is fully completed."

          2.   The following sentence is hereby added at the end of Section 1 of
the Option Agreement:  "The Construction Budget shown in Exhibit "Construction
Budget" shall not be increased by more than $50,000.00 without Buyer's prior
written consent.



          3.   The following Section 9(d) is added to the Option Agreement:

               "(d) Seller shall have paid all costs of any
                    nature relating to the ownership, development
                    and construction of the buildings and
                    improvements on the Property through the date
                    of Settlement and shall deliver evidence of
                    such payment to Buyer.  Seller shall execute
                    and deliver, and shall cause all contractors
                    to execute and deliver, all documents
                    reasonably required to effectuate Buyer's
                    takeover of the responsibility for such
                    construction, free and clear of any
                    pre-Settlement obligations or claims, which
                    documents shall be reasonably acceptable to
                    Seller and Buyer."

          4.   Exhibit "Construction Budget" attached hereto and made a part
hereof is hereby attached to and made part of the Option Agreement.

          5.   As amended by this Amendment, the Option Agreement shall remain
in full force and effect.




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     IN WITNESS WHEREOF, Seller and Buyer have executed this Amendment on the
day and year first above written.

WITNESS:                      CORPORATE OFFICE PROPERTIES, L.P., by its sole
                              general partner, Corporate Office Properties Trust


      /s/                     By:  /s/ CLAY W. HAMLIN, III     
- ---------------------------       --------------------------------------
                                   Clay W. Hamlin, III
                                   President and Chief Executive Officer


WITNESS:                      CONSTELLATION GATESPRING II, LLC, by
                              CPI Gatespring II, Inc., its sole member


    /s/                       By:  /s/ ROGER A. WAESCHE, JR.    
- ---------------------------       ------------------------------------
                                   Roger A. Waesche, Jr.
                                   Vice President
ASSENTED AND AGREED TO BY
CONSTELLATION PROPERTIES, INC.


By:        /s/                
   ---------------------------
     Vice President


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