Exhibit 99.1

Corporate Office Properties Trust

Certification by the Chief Executive Officer

Relating to a Periodic Report Containing Financial Statements

                I, Clay W. Hamlin, III, Chief Executive Officer of Corporate Office Properties Trust, a Maryland real estate investment trust (the “Company”), hereby certify, based on my knowledge, that:

                (1)           The Company’s annual report on Form 10-K for the period ended December 31, 2002 (the “Form 10-K”) fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; and

                (2)           The information contained in the Form 10-K fairly presents, in all material respects, the financial condition and results of operations of the Company.

*              *              *

/s/ Clay W. Hamlin, III
Clay W. Hamlin, III
Chief Executive Officer
Date:	March 27, 2003