EXHIBIT 1.1

                                9,700,000 SHARES

                        CORPORATE OFFICE PROPERTIES TRUST

                      COMMON SHARES OF BENEFICIAL INTEREST

                             UNDERWRITING AGREEMENT

                                                               February 27, 2002

CREDIT SUISSE FIRST BOSTON CORPORATION
A.G. EDWARDS & SONS, INC.
LEGG MASON WOOD WALKER INCORPORATED
MCDONALD INVESTMENTS INC.
     As Representatives of the Several Underwriters (the "Representatives"),
     c/o Credit Suisse First Boston Corporation
         Eleven Madison Avenue,
         New York, N.Y, 10010-3629
Dear Sirs:

     1. INTRODUCTORY. Corporate Office Properties Trust, a Maryland real estate
investment trust ("COMPANY"), proposes to issue and sell 823,828 of its common
shares of beneficial interest ("SECURITIES") and Constellation Real Estate, Inc.
("SELLING SHAREHOLDER") proposes to sell 8,876,172 outstanding Securities (such
9,700,000 Securities being hereinafter referred to as the "FIRM SECURITIES").
The Company also proposes to sell to the Underwriters, at the option of the
Underwriters, an aggregate of not more than 1,261,000 additional Securities as
set forth below (such 1,261,000 additional shares being hereinafter referred to
as the "OPTIONAL SECURITIES"). The Firm Securities and the Optional Securities
are herein collectively called the "OFFERED SECURITIES." The Company, Corporate
Office Properties, L.P., a Delaware limited partnership ("OPERATING
PARTNERSHIP") and the Selling Shareholder, hereby agree with the several
Underwriters named in Schedule I hereto ("UNDERWRITERS") as follows:

     2. REPRESENTATIONS AND WARRANTIES OF THE COMPANY, THE OPERATING PARTNERSHIP
AND THE SELLING SHAREHOLDER.

     (a) The Company and the Operating Partnership represent and warrant to, and
agree with, the several Underwriters that:

          (i) A registration statement (No. 333-71807) relating to the Offered
     Securities being sold by the Company, including a base prospectus, has been
     filed with the Securities and Exchange Commission (the "COMMISSION") under
     the Securities Act of 1933, as amended ("ACT"), and a registration
     statement (No. 333-59766) relating, among other things, to the Offered
     Securities being sold by the Selling Shareholder, including a base
     prospectus, has been filed with the Commission under the Act, and such
     registration statements (each an "INITIAL REGISTRATION STATEMENT," and
     together, the "INITIAL REGISTRATION STATEMENTS") have been declared
     effective. Post-effective amendments to the initial registration
     statements, including base prospectuses dated November 1, 2000 and May 17,
     2001 (each a "BASE PROSPECTUS," and together, the "BASE PROSPECTUSES"),
     have also been filed and declared effective under the Act. For purposes of
     this Agreement, "EFFECTIVE TIME" with respect to each initial registration
     statement means the date and time as of which the most recent
     post-effective amendment thereto filed prior to the execution and delivery
     of this Agreement, was declared effective by the



     Commission. "EFFECTIVE DATE" with respect to each initial registration
     statement means the date of the Effective Time thereof. Each initial
     registration statement, as amended at its Effective Time, including all
     material incorporated by reference therein, pursuant to the General
     Instructions of the Form on which it is filed and including all information
     (if any) deemed to be a part of the initial registration statement as of
     its Effective Time pursuant to RULE 430A(b) ("RULE 430A(b)") under the Act,
     is hereinafter referred to as a "REGISTRATION STATEMENT." The Base
     Prospectuses, together with the final prospectus supplement setting forth
     the final terms of the offering, sale and plan of distribution of the
     Offered Securities, as filed with the Commission pursuant to and in
     accordance with RULE 424(b) ("RULE 424(b)") under the Act and as included
     in a Registration Statement, including all material incorporated by
     reference in such prospectuses, is hereinafter referred to as the
     "PROSPECTUS." References to a "preliminary prospectus" mean the Base
     Prospectuses or together with the preliminary prospectus supplement
     relating to the Offered Securities. No document has been or will be
     prepared or distributed in reliance on Rule 434 under the Act. The Company
     meets the requirements for the use of Form S-3 under the Act. Registration
     Statement (No. 333-71807) meets the requirements of, and complies in all
     material respects with, Rule 415(a)(1)(x) under the Act, and Registration
     Statement (No. 333-59766) meets the requirements of, and complies in all
     material respects with, Rule 415(a)(1)(i) under the Act.

          (ii) If the Effective Time of either Registration Statement is prior
     to the execution and delivery of this Agreement: (i) on the Effective Date
     of such Registration Statement, the Registration Statement conformed in all
     material respects to the requirements of the Act and the rules and
     regulations of the Commission ("RULES AND REGULATIONS") and did not include
     any untrue statement of a material fact or omit to state any material fact
     required to be stated therein or necessary to make the statements therein
     not misleading and (ii) on the date of this Agreement, such Registration
     Statement conforms, and at the time of filing of the Prospectus pursuant to
     Rule 424(b) such Registration Statement together with the Prospectus will
     conform, in all material respects, to the requirements of the Act and the
     Rules and Regulations, and neither of such documents includes, or will
     include, any untrue statement of a material fact or omits, or will omit, to
     state any material fact required to be stated therein or necessary to make
     the statements therein not misleading, and with respect to the Prospectus
     only, in light of the circumstances in which they were made. The preceding
     sentence does not apply to statements in or omissions from a Registration
     Statement or the Prospectus based upon written information furnished to the
     Company by any Underwriter through the Representatives specifically for use
     therein, it being understood and agreed that the only such information is
     that described as such in Section 7(c) hereof.

          (iii) No stop order suspending the effectiveness of either
     Registration Statement or any part thereof has been issued and, to the
     knowledge of the Company, no proceeding for that purpose has been
     instituted or threatened by the Commission or by the state securities
     authority of any jurisdiction. No order preventing or suspending the use of
     the Prospectus has been issued and, to the knowledge of the Company, no
     proceeding for that purpose has been instituted or threatened by the
     Commission or by the state securities authority of any jurisdiction.

          (iv) The Company has been duly organized and is an existing real
     estate investment trust in good standing under the laws of the State of
     Maryland, with power and authority as a real estate investment trust to own
     its properties and conduct its business as described in the Prospectus; and
     the Company is duly qualified to do business


                                       2


     as a foreign corporation in good standing in all other jurisdictions in
     which its ownership or lease of property or the conduct of its business
     requires such qualification, except where the failure to be so qualified
     would not reasonably be expected to have a material adverse effect on (i)
     the condition (financial or other), business, properties, prospects, net
     worth or results of operations of the Company and its Subsidiaries (as
     hereinafter defined) taken as a whole, (ii) the issuance or validity of the
     Offered Securities or (iii) the consummation of any of the transactions
     contemplated by this Agreement to be performed by the Company and/or the
     Subsidiaries (individually or collectively, a "MATERIAL ADVERSE EFFECT").

          (v) Each subsidiary of the Company listed on Schedule II hereto
     ("SUBSIDIARIES") has been duly organized and is validly existing as a
     corporation, limited partnership or other legal entity, as the case may be,
     in good standing under the laws of its respective jurisdictions of
     incorporation or formation, with power and authority (corporate and other)
     to own its properties and conduct its business as described in the
     Prospectus; and each Subsidiary is duly qualified to do business as a
     foreign corporation, limited partnership or other legal entity, as the case
     may be, in good standing in all other jurisdictions in which such
     Subsidiary's ownership or lease of property or the conduct of such
     Subsidiary's business requires such qualification, except where the failure
     to be so qualified would not reasonably be expected to have a Material
     Adverse Effect. The issued and outstanding common and preferred units of
     limited partnership interest in the Operating Partnership ("UNITS") and
     other equity interests, as the case may be, of each of the Company's other
     Subsidiaries have been duly authorized and validly issued, are, with
     respect to corporate Subsidiaries, fully paid and nonassessable and, except
     as otherwise set forth in the Prospectus or reflected in the financial
     statements contained in, or incorporated by reference in, the Prospectus,
     are owned beneficially by the Company, directly or indirectly through one
     or more Subsidiaries, free and clear of any security interests, liens,
     encumbrances, equities or claims, except for security interests, liens,
     encumbrances, equities or claims pursuant to the terms of a bona fide
     financing transaction.

          (vi) Complete and correct copies of the declaration of trust and of
     the bylaws of the Company, the certificate of limited partnership and
     agreement of limited partnership of the Operating Partnership and the
     charter documents, partnership agreements and other organizational
     documents of the other Subsidiaries, as applicable, and all amendments
     thereto as have been requested by the Underwriters or their counsel have
     been delivered to the Underwriters or their counsel. The partnership
     agreement of the Operating Partnership, as amended, will have been duly
     authorized, executed and delivered by the Company, as the general partner
     and as a limited partner and (assuming it has been duly authorized,
     executed and delivered by each of the other parties thereto, and is a
     legal, valid and binding agreement of each such other party) in full force
     and effect, subject to (i) the effect of bankruptcy, insolvency, fraudulent
     conveyance, reorganization, moratorium or other similar laws now or
     hereafter in effect relating to or affecting the rights and remedies of
     creditors, (ii) the effect of general principles of equity, whether
     enforcement is considered in a proceeding in equity or at law, and the
     discretion of the court before which any proceeding therefore may be
     brought and (iii) the provisions of the Delaware Revised Uniform Limited
     Partnership Act.

          (vii) The Company has an authorized, issued and outstanding
     capitalization as set forth in the Prospectus. All of the issued and
     outstanding shares of beneficial interest of the Company have been duly
     authorized and validly issued and are fully paid and


                                       3


     nonassessable. The Offered Securities have been duly authorized and, when
     the Offered Securities have been delivered and paid for in accordance with
     this Agreement on each Closing Date (as hereinafter defined), such Offered
     Securities will have been validly issued, fully paid and nonassessable and
     will conform to the description thereof contained in the Prospectus, and at
     the First Closing Date (as hereinafter defined) and Optional Closing Date
     (as hereinafter defined), such descriptions will be, complete and accurate
     in all material respects; the shareholders of the Company have no
     preemptive rights with respect to the Offered Securities; and, except as
     set forth in the Company Registration Rights Agreements (as defined in the
     following sentence), no holder of securities of the Company has any right
     which has not been fully exercised or waived to require the Company to
     register the offer or sale of any securities owned by such holder under the
     Act in the public offering contemplated by this Agreement. The "COMPANY
     REGISTRATION RIGHTS AGREEMENTS" shall mean, collectively: (i) the Amended
     and Restated Registration Rights Agreement, dated March 16, 1998, of
     Corporate Office Properties Trust for the benefit of Holders of the
     Partnership Units and Preferred Units of Corporate Office Properties, L.P.
     and Holders of Common Shares of Beneficial Interest of Corporate Office
     Properties Trust; (ii) the Registration Rights Agreement, dated September
     28, 1998, by Corporate Office Properties Trust for the benefit of persons
     issued shares of its Common Shares of Beneficial Interest and Convertible
     Preferred Stock pursuant to the Contribution Agreement, the Asset
     Contribution Agreement and the Development Agreement, each dated May 14,
     1998; and (iii) the Registration Rights Agreement, dated January 25, 2001
     of Corporate Office Properties Trust for the benefit of Barony Trust
     Limited.

          (viii) Except for the Company Registration Rights Agreements, there
     are no contracts, agreements or understandings between the Company and any
     person granting such person the right to require the Company to file a
     registration statement under the Act with respect to any securities of the
     Company owned or to be owned by such person or to require the Company to
     include such securities in the securities registered pursuant to a
     Registration Statement or in any securities being registered pursuant to
     any other registration statement filed by the Company under the Act. Any
     notices required to be given under the Registration Rights Agreements were
     given and no person with rights thereunder, other then the Selling
     Shareholders, has exercised any such rights.

          (ix) Except as disclosed in the Prospectus or not disclosed because
     not material, the Company and its Subsidiaries do not have outstanding, and
     at the First Closing Date and Optional Closing Date will not have
     outstanding (A) securities or obligations of the Company or any of its
     Subsidiaries convertible into or exchangeable for any shares of beneficial
     interest of the Company or any such Subsidiary, (B) warrants, rights or
     options to subscribe for or purchase from the Company or any such
     Subsidiary any such shares of beneficial interest or any such convertible
     or exchangeable securities or obligations (except for options issued
     subsequent to January 31, 2002 under the Company's established stock option
     plans), or (C) obligations of the Company or any such Subsidiary to issue
     any shares of beneficial interest, any such convertible or exchangeable
     securities or obligations, or any such warrants, rights or options. The
     form of share certificates to be used to evidence the Offered Securities
     will be in due and proper form and will comply, in all material respects,
     with all applicable legal requirements. Other than shares of beneficial
     interest of the Company issuable upon (i) exercise of share options
     pursuant to the Company's stock-based plans for its employees and trustees,
     (ii) upon the redemption of Units, (iii) in connection with certain limited
     partnership interests in limited partnerships holding certain office
     properties retained by


                                       4


     Shidler Equities, L.P. and Clay W. Hamlin, III, or (iv) in connection with
     the conversion of either of the 5.5% Series A Convertible Preferred Share
     of Beneficial Interest, or the 4% Series D Convertible Preferred Shares of
     Beneficial Interest of the Company into Common Shares of Beneficial
     Interest of the Company, no shares of beneficial interest of the Company
     are reserved for any purpose, except as disclosed in the Prospectus.

          (x) The execution, delivery and performance of this Agreement by the
     Company and the Operating Partnership, the issuance, offering and sale of
     the Offered Securities to the Underwriters by the Company pursuant to this
     Agreement and the compliance by the Company and the Operating Partnership
     with the other provisions of this Agreement and the consummation of the
     other transactions herein contemplated to be performed by the Company and
     the Operating Partnership do not (i) require any material governmental
     license, permit, consent, approval, authorization or other order of,
     registration, filing or qualification with, any court or governmental body
     or agency except such as have been obtained or may be required under the
     Act and the Securities Exchange Act of 1934, as amended (the "EXCHANGE
     ACT"), securities, blue sky or real estate syndication laws of the various
     states, the bylaws and rules of the National Association of Securities
     Dealers, Inc. ("NASD") or the requirements of the New York Stock Exchange,
     Inc. ("NYSE"), (ii) result in the creation or imposition of any lien,
     charge or encumbrance upon any of the assets or properties of the Company
     or any of the Subsidiaries pursuant to the terms or provisions of, or
     conflict with or result in a breach or violation of any of the terms or
     provisions of, or constitute a default under (whether with or without the
     giving of notice or passage of time or both, would constitute a default
     under any of the foregoing), or give any other party a right to terminate
     any of its obligations under, or result in the acceleration of any
     obligation under, the charter, declaration of trust, bylaws, partnership
     agreement or other organizational document of the Company or any of the
     Subsidiaries or in the performance or observance of any obligation,
     covenant, agreement or condition contained in any indenture, loan
     agreement, mortgage, bond, debenture, note agreement, joint venture or
     partnership agreement, lease or other agreement or instrument that is
     material to the Company and the Subsidiaries, taken as a whole, to which
     the Company or any of the Subsidiaries is a party or by which the Company
     or any of the Subsidiaries or their respective property is bound or, (iii)
     violate or conflict with any applicable law or any rule, regulation,
     judgment, order, statute, administrative regulation or decree of any court
     or any governmental body or agency (foreign or domestic) having
     jurisdiction over the Company, any of the Subsidiaries or their respective
     property, in each case except for liens, charges, encumbrances, breaches,
     violations, defaults, rights to terminate or accelerate obligations, or
     conflicts, the imposition or occurrence of which would not have a Material
     Adverse Effect.

          (xi) Each of the Company and the Operating Partnership has full trust
     or partnership power, as the case may be, to enter into this Agreement, and
     to carry out all of the terms and provisions hereof to be carried out by
     them. This Agreement has been duly and validly authorized, executed and
     delivered by each of the Company and the Operating Partnership, and
     constitutes a valid and binding agreement of each of the Company and the
     Operating Partnership, and assuming due authorization, execution and
     delivery by the Underwriters, is enforceable against the Company and the
     Operating Partnership, in accordance with the terms hereof subject to (i)
     the effect of bankruptcy, insolvency, fraudulent conveyance,
     reorganization, moratorium or other similar laws now or hereafter in effect
     relating to or affecting the rights and remedies of creditors and (ii) the
     effect of general principles of equity, whether enforcement is considered
     in a


                                       5


     proceeding in equity or at law, and the discretion of the court before
     which any proceeding therefor may be brought.

          (xii) When the Offered Securities are delivered and paid for pursuant
     to this Agreement on each Closing Date, the Company and each of its
     Subsidiaries will have good and marketable title in fee simple to all items
     of real property and valid title to all personal property and assets owned
     by each of them, in each case free and clear of any security interests,
     liens, encumbrances, equities, claims and other defects, except such as
     where the failure to have such title would not result in a Material Adverse
     Effect or would not materially and adversely affect the value of such
     property or materially interfere with the use made or proposed to be made
     of such property by the Company or such Subsidiary (except in each case
     liens securing indebtedness of the Company or its Subsidiaries as reflected
     in its financial statements included in the Prospectus, or mortgage
     indebtedness incurred by the Company in the ordinary course of its
     business), and any real property and buildings held under lease by the
     Company or any such Subsidiary are held under valid, subsisting and
     enforceable leases, except where the invalidity, non-subsistence or
     non-enforceability would not result in a Material Adverse Effect or would
     not materially interfere with the use made or proposed to be made of such
     property and buildings by the Company or such Subsidiary, in each case
     except as described in or contemplated by the Prospectus. To the knowledge
     of the Company and the Operating Partnership, except as disclosed in the
     Prospectus: (i) no lessee of any portion of the properties is in material
     default under any of the leases governing such properties and there is no
     event which, but for the passage of time or the giving of notice, or both,
     would constitute a default under any of such leases, except in each case
     such defaults that would not have a Material Adverse Effect; (ii) the
     current use and occupancy of each of the properties complies in all
     material respects with all applicable codes and zoning laws and
     regulations, except for such failures to comply which would not
     individually or in the aggregate have a Material Adverse Effect; and (iii)
     there is no pending or threatened condemnation, zoning change,
     environmental or other proceeding or action that will in any material
     respect affect the size of, use of, improvements on, construction on, or
     access to the properties except such proceedings or actions that would not
     have a Material Adverse Effect.

          (xiii) The Company and its Subsidiaries possess adequate certificates,
     authorities, consents, authorizations or permits issued by appropriate
     governmental agencies or bodies necessary to conduct the business now
     operated by them, have complied, in all material respects, with the laws,
     regulations and orders known by them to be applicable to them or their
     respective businesses and properties and have not received any notice of
     proceedings relating to the revocation or modification of any such
     certificate, authority, consents, authorizations or permit that, if
     determined adversely to the Company or any of its Subsidiaries, would
     individually or in the aggregate have a Material Adverse Effect.

          (xiv) No labor dispute with the employees of the Company or any
     Subsidiary exists or, to the knowledge of the Company, is threatened or
     imminent that might have a Material Adverse Effect.

          (xv) The Company and its Subsidiaries own, possess, license or can
     acquire on reasonable terms, adequate trademarks, trade names, licenses,
     and other rights to inventions, know-how, patents, copyrights, confidential
     or proprietary information and other intellectual property (collectively,
     "INTELLECTUAL PROPERTY RIGHTS") necessary to


                                       6


     conduct the business now operated by them, or presently employed by them,
     and have not received any notice of infringement of or conflict with
     asserted rights of others with respect to any intellectual property rights
     that, if determined adversely to the Company or any of its Subsidiaries,
     would individually or in the aggregate have a Material Adverse Effect.

          (xvi) Except for activities, conditions, circumstances or matters that
     would not have a Material Adverse Effect, (A) to the knowledge of the
     Company, after due inquiry, neither the Company nor any of the Subsidiaries
     has violated (i) any foreign, federal, state or local law or regulation
     relating to the protection of human health and safety, the environment or
     hazardous or toxic substances or wastes, pollutants or contaminants
     ("ENVIRONMENTAL LAWS") (and the Company and the Subsidiaries are in
     compliance with all requirements of applicable permits, licenses, approvals
     or other Authorizations issued pursuant to Environmental Laws), (ii) any
     provisions of the Employee Retirement Income Security Act of 1974, as
     amended or (iii) any provisions of the Foreign Corrupt Practices Act, or
     the rules and regulations promulgated thereunder; (B) to the knowledge of
     the Company and the Subsidiaries, after due inquiry, none of the Company or
     the Subsidiaries has caused or suffered to occur any Release (as
     hereinafter defined) of any Hazardous Substance (as hereinafter defined)
     into the Environment (as hereinafter defined) on, in, under or from any
     property, and no condition exists on, in, under or adjacent to any property
     that would reasonably be expected to result in the incurrence of
     liabilities under, or any violations of, any Environmental Law or give rise
     to the imposition of any Lien (as hereinafter defined), under any
     Environmental Law; (C) none of the Company or the Subsidiaries has received
     any written notice of a material claim under or pursuant to any
     Environmental Law or under common law pertaining to Hazardous Substances
     on, in, under or originating from any property; (D) none of the Company or
     any of the Subsidiaries has actual knowledge of, or received any written
     notice from any Governmental Authority (as hereinafter defined) claiming,
     any material violation of any Environmental Law or a determination to
     undertake and/or request the investigation, remediation, clean-up or
     removal of any Hazardous Substance released into the Environment on, in,
     under or from any property; and (E) no property now or heretofore owned or
     leased by the Company or any of the Subsidiaries is included or, to the
     knowledge of the Company and the Subsidiaries, after due inquiry, proposed
     for inclusion on the National Priorities List issued pursuant to CERCLA (as
     hereinafter defined) by the United States Environmental Protection Agency
     (the "EPA"), or included on the Comprehensive Environmental Response,
     Compensation, and Liability Information System database maintained by the
     EPA, and none of the Company and the Subsidiaries has actual knowledge that
     any property has otherwise been identified in a published writing by the
     EPA as a potential CERCLA removal, remedial or response site or, to the
     knowledge of the Company and the Subsidiaries, is included on any similar
     list of potentially contaminated sites pursuant to any other Environmental
     Law.

          As used herein, "HAZARDOUS SUBSTANCE" shall include any hazardous
     substance, hazardous waste, toxic substance, pollutant or hazardous
     material, including, without limitation, oil, petroleum or any
     petroleum-derived substance or waste, asbestos or asbestos-containing
     materials, PCBs, pesticides, explosives, radioactive materials, dioxins,
     urea formaldehyde insulation or any constituent of any such substance,
     pollutant or waste which is subject to regulation under any Environmental
     Law (including, without limitation, materials listed in the United States
     Department of Transportation Optional Hazardous Material Table, 49 C.F.R.
     ss. 172.101, or in the EPA's List of Hazardous Substances and Reportable
     Quantities, 40 C.F.R. Part 302); "ENVIRONMENT" shall mean


                                       7


     any surface water, drinking water, ground water, land surface, subsurface
     strata, river sediment, buildings, structures, and indoor and outdoor air;
     "ENVIRONMENTAL LAW" shall mean the Comprehensive Environmental Response,
     Compensation and Liability Act of 1980, as amended (42 U.S.C. ss. 9601 et
     seq.) ("CERCLA"), the Resource Conservation and Recovery Act of 1976, as
     amended (42 U.S.C. ss. 6901, et seq.), the Clean Air Act, as amended (42
     U.S.C. ss. 7401, et seq.), the Clean Water Act, as amended (33 U.S.C. ss.
     1251, et seq.), the Toxic Substances Control Act, as amended (15 U.S.C. ss.
     2601, et seq.), the Occupational Safety and Health Act of 1970, as amended
     (29 U.S.C. ss. 651, et seq.), the Hazardous Materials Transportation Act,
     as amended (49 U.S.C. ss. 1801, et seq.), and all other federal, state and
     local laws, ordinances, regulations, rules and orders relating to the
     protection of the environment or of human health from environmental
     effects; "GOVERNMENTAL AUTHORITY" shall mean any federal, state or local
     governmental office, agency or authority having the duty or authority to
     promulgate, implement or enforce any Environmental Law; "LIEN" shall mean,
     with respect to any property, any mortgage, deed of trust, pledge, security
     interest, lien, encumbrance, penalty, fine, charge, assessment, judgment or
     other liability in, on or affecting such property; and "RELEASE" shall mean
     any spilling, leaking, pumping, pouring, emitting, emptying, discharging,
     injecting, escaping, leaching, dumping, emanating or disposing of any
     Hazardous Substance into the Environment, including, without limitation,
     the abandonment or discard of barrels, containers, tanks (including,
     without limitation, underground storage tanks) or other receptacles
     containing or previously containing and containing a residue of any
     Hazardous Substance.

          (xvii) To the knowledge of the Company, none of the environmental
     consultants which prepared environmental and asbestos inspection reports
     with respect to any of the properties was employed for such purpose on a
     contingent basis or has any substantial interest in the Company or any of
     the Subsidiaries, and none of them nor any of their directors, officers or
     employees is connected with the Company or any of the Subsidiaries as a
     promoter, selling agent, voting trustee, director, officer or employee.

          (xviii) Except as disclosed in the Prospectus, after due inquiry,
     there are no pending actions, suits or proceedings against or, to the
     knowledge of the Company, affecting the Company, any of its Subsidiaries or
     any of their respective properties or any of their respective officers or
     trustees that, if determined adversely to the Company or any of its
     Subsidiaries or any of their respective officers or trustees, would
     individually or in the aggregate have a Material Adverse Effect, or which
     are otherwise material in the context of the sale of the Offered Securities
     and/or are required to be described in the Registration Statements or
     Prospectus; and, to the knowledge of the Company, no such actions, suits or
     proceedings are threatened or contemplated, in each case, before or by any
     federal or state court, commission, regulatory body, administrative agency
     or other governmental body, domestic or foreign, having jurisdiction over
     the Company, any of its Subsidiaries or assets; and no contract, statute,
     regulation or other document is required to be described in the
     Registration Statements or the Prospectus or to be filed as an exhibit to
     the Registration Statements that is not described therein or filed as
     required.

          (xix) The consolidated financial statements and schedules and notes
     thereto of the Company and its consolidated Subsidiaries included in the
     Registration Statements and the Prospectus comply in all material respects
     with the requirements of the Act and the Exchange Act, as applicable, and
     Item 301 of Regulation S-K promulgated by the Commission, and fairly
     present the financial position of the Company and its consolidated
     Subsidiaries and the results of operations and changes in financial
     condition


                                       8


     as of the dates and periods therein specified. Such financial statements,
     schedules and notes have been prepared in accordance with generally
     accepted accounting principles consistently applied throughout the periods
     involved (except as otherwise noted therein). The selected financial data
     set forth under the caption "SELECTED FINANCIAL INFORMATION" in the
     Prospectus fairly present, on the basis stated in the Prospectus, the
     information included therein. Except as otherwise noted in the Prospectus,
     as adjusted financial information included in the Prospectus has been
     prepared in accordance with the applicable requirements of the Act and any
     applicable U.S. accounting guidelines, and includes where required all
     adjustments necessary to present fairly the as adjusted financial condition
     of the Company and the Subsidiaries presented or included at the respective
     dates indicated and the results of operations and cash flows for the
     respective periods specified; and the assumptions used in preparing the as
     adjusted financial statements included in the Registration Statements and
     the Prospectus provide a reasonable basis for presenting the significant
     effects directly attributable to the transactions or events described
     therein, the related as adjusted adjustments give appropriate effect to
     those assumptions, and the as adjusted columns therein reflect the proper
     application of those adjustments to the corresponding historical financial
     statement amounts. No other financial statements (or schedules) of the
     Company or any predecessor of the Company are required by the Act to be
     included in the Registration Statements or the Prospectus.

          (xx) PricewaterhouseCoopers LLP, who have certified certain financial
     statements of the Company and its consolidated subsidiaries and delivered
     their report with respect to the audited consolidated financial statements
     and schedules included in the Registration Statements and the Prospectus,
     are independent public accountants as required by the Act and the Exchange
     Act.

          (xxi) Subsequent to the respective dates as of which information is
     given in the Registration Statements or the Prospectus and prior to the
     First Closing Date, (i) neither the Company nor any of its Subsidiaries has
     sustained any material casualty loss, condemnations or interference with
     their respective businesses or properties from fire, flood, hurricane,
     accident or other calamity, whether or not covered by insurance, or from
     any labor dispute or any legal or governmental proceeding, (ii) there has
     not been any material adverse change, or any development or event that
     would be reasonably likely to result in a material adverse change, in the
     condition (financial or otherwise), management, business, properties,
     prospects, net worth, or results of operations of the Company or any of its
     Subsidiaries, taken as a whole, except in each case as described in or
     contemplated by the Prospectus and (iii) except as disclosed in or
     contemplated by the Prospectus or otherwise consistent with past practice,
     there has been no dividend or distribution of any kind declared, paid or
     made by the Company on any class of its capital stock.

          (xxii) The Company is not and, after giving effect to the offering and
     sale of the Offered Securities and the application of the proceeds thereof
     as described in the Prospectus, will not be an "INVESTMENT COMPANY" as
     defined in the Investment Company Act of 1940, as amended.

          (xxiii) The Company has not, directly or indirectly, (i) taken any
     action designed to cause or to result in, or that has constituted or which
     might reasonably be expected to constitute, the stabilization or
     manipulation of the price of any security of the Company to facilitate the
     sale or resale of the Offered Securities or (ii) since the filing of


                                       9


     each respective Registration Statement (A) sold, bid for, purchased, or
     paid anyone any compensation for soliciting purchases of, the Offered
     Securities or (B) paid or agreed to pay to any person any compensation for
     soliciting another to purchase any other securities of the Company.

          (xxiv) The Company has not distributed and, prior to the later of (i)
     the First Closing Date and (ii) the completion of the distribution of the
     Offered Securities, will not distribute any offering material in connection
     with the offering and sale of the Offered Securities other than the
     Registration Statements or any amendment thereto, or the Prospectus or any
     amendment or supplement thereto, or other materials, if any permitted by
     the Act.

          (xxv) Subsequent to the respective dates as of which information is
     given in the Registration Statements and the Prospectus, (1) the Company
     and its Subsidiaries have not incurred any material liability or
     obligation, direct or contingent, nor entered into any material
     transaction, in each case, not in the ordinary course of business; (2) the
     Company has not purchased any of its outstanding shares of beneficial
     interest, nor declared, paid or otherwise made any dividend or distribution
     of any kind on its shares of beneficial interest except in the ordinary
     course of business consistent with past practices; and (3) there has not
     been any material change in the capitalization, equity, short-term debt or
     long-term debt of the Company and its consolidated Subsidiaries, except in
     each case as described in or contemplated by the Prospectus.

          (xxvi) The Company and each of its Subsidiaries are insured by
     property, title, casualty and liability insurers of recognized financial
     responsibility against such losses and risks and in such amounts as are
     prudent and customary in the businesses in which they are engaged; neither
     the Company nor any such Subsidiary has been refused any insurance coverage
     sought or applied for; and neither the Company nor any such Subsidiary has
     any reason to believe that it will not be able to renew its existing
     insurance coverage as and when such coverage expires or to obtain similar
     coverage from similar insurers as may be necessary to continue its business
     at a cost that would not result in Material Adverse Effect, except in such
     instances where the tenant is carrying such insurance or the tenant is
     self-insuring such risks and except as described in or contemplated by the
     Prospectus.

          (xxvii) No Subsidiary of the Company is currently prohibited, directly
     or indirectly, from paying any dividends to the Company, from making any
     other distribution on the equity interest in such Subsidiary held by the
     Company, from repaying to the Company any loans or advances to such
     Subsidiary from the Company or from transferring any of such Subsidiary's
     property or assets to the Company or any other Subsidiary of the Company,
     except as described in or contemplated by the Prospectus or pursuant to the
     terms of its outstanding securities or a bona fide financing transaction.

          (xxviii) The Company and each of its Subsidiaries has filed all
     foreign, federal, state and local income tax returns that are required to
     be filed or has requested extensions thereof (except in any case in which
     the failure so to file would not have a Material Adverse Effect) and has
     paid all taxes required to be paid by it and any other assessment, fine or
     penalty levied against it, to the extent that any of the foregoing is due
     and payable, except for any such tax, assessment, fine or penalty that is
     currently being contested in good faith or as described in or contemplated
     by the Prospectus or which would not result in a Material Adverse Effect.


                                       10


          (xxix) Commencing with the Company's taxable year ended December 31,
     1994, the Company was organized and has operated in conformity with the
     requirements for qualification and taxation as a real estate investment
     trust ("REIT") under Sections 856 through 860 of the Internal Revenue Code
     of 1986, as amended (the "CODE"), and its proposed method of operations
     will enable it to continue to meet the requirements for qualification and
     taxation as a REIT. All statements in the Prospectus regarding the
     Company's qualification as a REIT are true, complete and correct in all
     material respects.

          (xxx) Except for the shares of capital stock or other equity interests
     of each of the Subsidiaries owned by the Company and such Subsidiaries,
     neither the Company nor any such Subsidiary owns any shares of stock or any
     other equity securities of any corporation or has any equity interest in
     any firm, partnership, association or other entity, except as described in
     or contemplated by the Prospectus.

          (xxxi) The Company and each of its Subsidiaries maintain a system of
     internal accounting controls sufficient to provide reasonable assurance
     that (1) transactions are executed in accordance with management's general
     or specific authorizations; (2) transactions are recorded as necessary to
     permit preparation of financial statements in conformity with generally
     accepted accounting principles and to maintain asset accountability; (3)
     access to assets, financial and corporate books and records is permitted
     only in accordance with management's general or specific authorization; and
     (4) the recorded accountability for assets is compared with the existing
     assets at reasonable intervals and appropriate action is taken with respect
     to any differences.

          (xxxii) Neither the Company nor any of the Subsidiaries is in breach
     or violation of its respective declaration of trust, charter, bylaws,
     partnership agreement or other organizational document, as the case may be,
     or in default in the performance of any obligation, agreement, covenant or
     condition contained in any indenture, loan agreement, mortgage, bond,
     debenture, note agreement, joint venture or partnership agreement, lease or
     other agreement or instrument that is material to the Company and the
     Subsidiaries, taken as a whole, and to which the Company or any of the
     Subsidiaries is a party or by which the Company or any of the Subsidiaries
     or their respective property is bound (and there is no event which, whether
     with or without the giving of notice or passage of time or both, would
     constitute a default under any of foregoing), where such breach, violation
     or default would have a Material Adverse Effect.

          (xxxiii) Since January 1, 1998, the Company has timely filed all
     documents required to be filed by it under the Exchange Act.

          (xxxiv) No relationship, direct or indirect, exists between or among
     the Company or the Subsidiaries on the one hand, and the trustees,
     directors, officers, shareholders, customers or suppliers of the Company or
     the Subsidiaries on the other hand, which is required by the Act or the
     rules of the NASD to be described in the Registration Statements and the
     Prospectus which is not so described.

          (xxxv) There are no contracts, agreements, letters of intent,
     understandings or any other documents relating to the pending acquisition
     of any real property by the Company or the Operating Partnership that are
     required to be disclosed in the Prospectus and that are not so disclosed.



                                       11


     (b) The Selling Shareholder represents and warrants to, and agrees with,
the several Underwriters that:

          (i) The Selling Shareholder has and on each Closing Date hereinafter
     mentioned will have valid and unencumbered title to the Offered Securities
     to be delivered by the Selling Shareholder on such Closing Date and full
     right, power and authority to enter into this Agreement and to sell,
     assign, transfer and deliver the Offered Securities to be delivered by the
     Selling Shareholder on such Closing Date hereunder; and upon the delivery
     of and payment for the Offered Securities on each Closing Date hereunder
     the several Underwriters will acquire valid and unencumbered title to the
     Offered Securities to be delivered by the Selling Shareholder on such
     Closing Date free and clear of any security interest, mortgage, pledge,
     lien, charge, claim, equity or encumbrance of any kind, other than pursuant
     to this Agreement; and upon delivery of such Offered Securities and payment
     of the purchase price therefor as herein contemplated, assuming each such
     Underwriter has no notice of any adverse claim, each of the Underwriters
     will receive valid title to the Offered Securities purchased by it from the
     Selling Shareholder, free and clear of any security interest, mortgage,
     pledge, lien, charge, claim, equity or encumbrance of any kind.

          (ii) The execution and delivery of this Agreement and the sale and
     delivery of the Offered Securities to be sold by the Selling Shareholder
     and the consummation of the transactions contemplated herein and compliance
     by the Selling Shareholder with its obligations hereunder have been duly
     authorized by the Selling Shareholder and do not and will not, whether with
     or without the giving of notice or passage of time or both, conflict with
     or constitute a breach of, or default under, or result in the creation or
     imposition of any lien, charge or encumbrance upon the Offered Securities
     to be sold by the Selling Shareholder pursuant to any contract, indenture,
     mortgage, deed of trust, loan or credit agreement, note, license, lease or
     other agreement or instrument to which the Selling Shareholder is a party
     or by which the Selling Shareholder may be bound, nor will such action
     result in any violation of the provisions of the charter or by-laws or
     other organizational instrument of the Selling Shareholder, if applicable,
     or any applicable treaty, law, statute, rule, regulation, judgment, order,
     writ or decree of any government, government instrumentality or court,
     domestic or foreign, having jurisdiction over the Selling Shareholder or
     any of its properties.

          (iii) The Selling Shareholder has duly executed and delivered this
     Agreement, and assuming the due authorization, execution and delivery by
     the other parties hereto, this Agreement will be the valid and binding
     agreement of the Selling Shareholder, enforceable against the Selling
     Shareholder in accordance with its terms, subject to (i) the effect of
     bankruptcy, insolvency, fraudulent conveyance, reorganization, moratorium
     or other similar laws now or hereafter in effect relating to or affecting
     the rights and remedies of creditors and (ii) the effect of general
     principles of equity, whether enforcement is considered in a proceeding in
     equity or at law, and the discretion of the court before which any
     proceeding therefor may be brought.

          (iv) If the Effective Time of the Registration Statement relating to
     the Offered Securities being sold by the Selling Shareholder is prior to
     the execution and delivery of this Agreement: (i) on the Effective Date of
     such Registration Statement, the Registration Statement did not include any
     untrue statement of a material fact or omit to state any material fact
     required to be stated therein or necessary to make the statements therein
     not misleading and (ii) on the date of this Agreement, such Registration


                                       12


     Statement, and at the time of filing of the Prospectus pursuant to Rule
     424(b) such Registration Statement and the Prospectus do not include, or
     will not include, any untrue statement of a material fact or omits, or will
     not omit, to state any material fact required to be stated therein or
     necessary to make the statements therein not misleading, and with respect
     to the Prospectus only, in light of the circumstances in which they were
     made. The preceding sentence applies only to the extent statements in, or
     omissions from, the Registration Statement or the Prospectus are based upon
     written information furnished to the Company by the Selling Shareholder
     specifically for use therein.

          (v) No filing with, or consent, approval, authorization, order,
     registration, qualification or decree of, any court or governmental
     authority or agency, domestic or foreign, is necessary or required for the
     performance by the Selling Shareholder of its obligations hereunder or in
     connection with the sale and delivery of the Offered Securities hereunder
     or the consummation of the transactions contemplated by this Agreement,
     except such as may have previously been made or obtained or as may be
     required under the Act or the Rules and Regulations or state securities
     laws.

          (vi) Except as disclosed in the Prospectus or pursuant to this
     Agreement, there are no contracts, agreements or understandings between the
     Selling Shareholder and any person that would give rise to a valid claim
     against the Selling Shareholder or any Underwriter for a brokerage
     commission, finder's fee or other like payment in connection with this
     offering.

          (vii) The Selling Shareholder has not taken, and will not take,
     directly or indirectly, any action which is designed to or which has
     constituted or which might reasonably be expected to cause or result in
     stabilization or manipulation of the price of any security of the Company
     to facilitate the sale or resale of the Offered Securities.

     3. PURCHASE, SALE AND DELIVERY OF OFFERED SECURITIES. On the basis of the
representations, warranties and agreements herein contained, but subject to the
terms and conditions herein set forth, the Company and the Selling Shareholder
agree, severally and not jointly, to sell to the Underwriters, and the
Underwriters agree, severally and not jointly, to purchase from the Company and
the Selling Shareholder, at a purchase price of $12.04 per share, the respective
numbers of shares of Firm Securities set forth below the caption "COMPANY" or
"SELLING SHAREHOLDER," as the case may be, and opposite the names of the
Underwriters in Schedule I hereto.

     The Company and the Selling Shareholder will deliver the Firm Securities,
with transfer taxes thereon duly paid, to the Representatives in book entry form
through the facilities of The Depository Trust Company ("DTC") for the
respective accounts of the Underwriters against payment of the purchase price in
Federal (same day) funds by wire transfer to an account of the Company at First
Union Bank in Baltimore, Maryland, in connection with the closing of such
transactions, at the office of Morgan, Lewis & Bockius LLP, Philadelphia,
Pennsylvania, at 10:00 A.M., New York time, on March 5, 2002, or at such other
time not later than seven full business days thereafter as Credit Suisse First
Boston Corporation ("CSFBC") and the Company determine, such time being herein
referred to as the "FIRST CLOSING DATE." For purposes of Rule 15c6-1 under the
Exchange Act, the First Closing Date (if later than the otherwise applicable
settlement date) shall be the settlement date for payment of funds and delivery
of securities for all the Offered Securities sold pursuant to the offering.
Prior to the First Closing Date, the Company will also deliver the form of fully
registered global certificate that will be deposited with DTC for the Firm
Securities that the several Underwriters have agreed to purchase hereunder.


                                       13



     In addition, upon written notice from CSFBC given to the Company from time
to time not more than 30 days subsequent to the date of the Prospectus (or, if
such 30th day shall be a Saturday or Sunday or a holiday, on the next business
day thereafter when the NYSE is open for trading), the Underwriters may purchase
all or less than all of the Optional Securities at the per share purchase price
(including any accumulated dividends thereon to the related Optional Closing
Date (as hereinafter defined)) to be paid for the Firm Securities. The
Underwriters shall not be under any obligation to purchase any of the Optional
Securities prior to the exercise of such option. Such Optional Securities shall
be purchased from the Company for the account of each Underwriter in the same
proportion as the number of shares of Firm Securities set forth opposite such
Underwriter's name bears to the total number of shares of Firm Securities
(subject to adjustment by CSFBC to eliminate fractions) and may be purchased by
the Underwriters only for the purpose of covering over-allotments made in
connection with the sale of the Firm Securities. No Optional Securities shall be
sold or delivered unless the Firm Securities previously have been, or
simultaneously are, sold and delivered. The right to purchase the Optional
Securities or any portion thereof may be exercised from time to time and to the
extent not previously exercised may be surrendered and terminated at any time
upon notice by CSFBC to the Company and the Selling Shareholder.

     Each time for the delivery of and payment for the Optional Securities,
being herein referred to as an "OPTIONAL CLOSING DATE," which may be the First
Closing Date (the First Closing Date and each Optional Closing Date, if any,
being sometimes referred to as a "CLOSING DATE"), shall be determined by CSFBC
but shall be not later than five (5) full business days after written notice of
election to purchase Optional Securities is given. The Company will deliver the
Optional Securities being purchased, with transfer taxes thereon duly paid, to
the Representatives in book entry form through the facilities of the DTC on each
Optional Closing Date for the accounts of the several Underwriters against
payment of the purchase price in Federal (same day) funds by wire transfer to an
account of the Company, in connection with the closing of the transactions, at
the above office. Prior to each Optional Closing Date, the Company will also
deliver the form of fully registered global certificate that will be deposited
with DTC for the Optional Securities that the several Underwriters have agreed
to purchase hereunder.

     4. OFFERING BY UNDERWRITERS. It is understood that the several Underwriters
propose to offer the Offered Securities for sale to the public as set forth in
the Prospectus.

     5. CERTAIN AGREEMENTS OF THE COMPANY, THE OPERATING PARTNERSHIP AND THE
SELLING SHAREHOLDER. The Company, the Operating Partnership and, as to Section
5(k) only, the Selling Shareholder, agree with the several Underwriters that:

          (a) The Company will file the final Prospectus with the Commission
     pursuant to and in accordance with subparagraph (5) of Rule 424(b) not
     later than the second business day following the execution and delivery of
     this Agreement). The Company will advise CSFBC promptly of any such filing
     pursuant to Rule 424(b).

          (b) The Company will advise CSFBC promptly of any proposal to amend or
     supplement the Registration Statements as filed or the related Prospectus
     and will not effect such amendment or supplementation without CSFBC's
     consent which shall not be unreasonably withheld. The Company will prepare
     and file with the Commission, in accordance with the rules and regulations
     of the Commission, promptly upon request by the Representatives or counsel
     for the Underwriters, any amendments to the Registration Statements or
     amendments or supplements to the Prospectus that may be necessary or
     advisable in connection with the distribution of the Offered Securities by
     the several Underwriters, and will use its best efforts to cause any such
     amendment to the Registration Statements to be declared effective by the
     Commission as promptly as possible. The Company will also advise CSFBC
     promptly of the effectiveness of the


                                       14


     Registration Statements (if its Effective Time is subsequent to the
     execution and delivery of this Agreement) and of any amendment or
     supplementation of the Registration Statements or the Prospectus and of the
     institution by the Commission of any stop order proceedings in respect of
     the Registration Statements and of the suspension of the qualification of
     the Offered Securities for offering or sale in any jurisdiction and will
     use its best efforts to prevent the issuance of any such stop order and to
     obtain as soon as possible its lifting, if issued.

          (c) The Company will advise CSFBC, promptly after receiving notice or
     obtaining knowledge thereof and, if requested by the Underwriters, to
     confirm such advice in writing, of (i) the issuance by the Commission of
     any stop order suspending the effectiveness of the Registration Statements
     or any Registration Statement filed under Rule 462(b) ("RULE 462(b)") under
     the Act or any post-effective amendment thereto or any order directed at
     any document incorporated by reference in the Registration Statements or
     the Prospectus or any amendment or supplement thereto or any order
     preventing or suspending the use of any Prospectus or any amendment or
     supplement thereto, (ii) the suspension of the qualification of the Offered
     Securities for offering or sale in any jurisdiction, (iii) the institution,
     threatening or contemplation of any proceeding for any such purpose, (iv)
     the effectiveness of any amendment to the Registration Statements or any
     Rule 462(b) Registration Statement, the transmittal to the Commission for
     filing of any Prospectus or other supplement or amendment thereto to be
     filed pursuant to the Act, any request made by the Commission for amending
     the Registration Statements or any Rule 462(b) Registration Statement, for
     amending or supplementing any preliminary prospectus or the Prospectus or
     for additional information or (v) the happening of any event during the
     period referred to in Section 5(d) below which makes any statement of a
     material fact made in the Registration Statements or Prospectus untrue or
     which requires any additions to or changes in the foregoing in order to
     make the statements therein not misleading. The Company will use its best
     efforts to prevent the issuance of any such stop order and, if any such
     stop order is issued, to obtain the withdrawal or lifting thereof as
     promptly as possible.

          (d) At any time when a prospectus relating to the Offered Securities
     is required to be delivered under the Act in connection with sales by any
     Underwriter or dealer, the Company (i) will comply with all requirements
     imposed upon it by the Act and the Exchange Act to the extent necessary to
     permit the continuance of sales of or dealings in the Offered Securities in
     accordance with the provisions hereof and of the Prospectus, as then
     amended or supplemented, (ii) will not file with the Commission the
     Prospectus, any amendment or supplement thereto or any amendment to the
     Registration Statements or any Rule 462(b) Registration Statement of which
     the Representatives shall not previously have been advised and furnished
     with a copy for a reasonable period of time prior to the proposed filing
     and as to which filing the Representatives shall not have given their
     consent which shall not be unreasonably withheld, and (iii) if any event
     occurs as a result of which the Prospectus as then amended or supplemented
     would include an untrue statement of a material fact or omit to state any
     material fact necessary to make the statements therein, in the light of the
     circumstances under which they were made, not misleading, or if it is
     necessary at any time to amend the Prospectus to comply with the Act, will
     promptly notify CSFBC of such event and will promptly prepare and file with
     the Commission, at its own expense, an amendment or supplement which will
     correct such statement or omission or an amendment which will effect such
     compliance. Neither CSFBC's consent to, nor the Underwriters' delivery of,
     any such amendment or supplement shall constitute a waiver of any of the
     conditions set forth in Section 6.

          (e) As soon as practicable, but not later than the Availability Date
     (as hereinafter defined), the Company will make generally available to its
     securityholders an earnings statement covering a period of at least 12
     months beginning after the Effective Date of each Initial


                                       15


     Registration Statement which will satisfy the provisions of Section 11(a)
     of the Act. For the purpose of the preceding sentence, "AVAILABILITY DATE"
     means the 45th day after the end of the fourth fiscal quarter following the
     fiscal quarter that includes such Effective Date, except that, if such
     fourth fiscal quarter is the last quarter of the Company's fiscal year,
     "AVAILABILITY DATE" means the 90th day after the end of such fourth fiscal
     quarter.

          (f) The Company will furnish, without charge, to the Representatives
     copies of each Registration Statement, each related preliminary prospectus
     and each Prospectus, and, so long as a prospectus relating to the Offered
     Securities is required to be delivered under the Act in connection with
     sales by any Underwriter or dealer, the Prospectus and all amendments and
     supplements to such documents (in each case including exhibits thereto), in
     each case in such quantities as CSFBC requests. The Prospectus shall be so
     furnished on or prior to 3:00 P.M., New York time, on the business day
     following the later of the execution and delivery of this Agreement or the
     Effective Time of each Registration Statement. All other documents shall be
     so furnished as soon as available. The Company will pay the expenses of
     printing and distributing to the Underwriters all such documents.

          (g) The Company will arrange for the registration or qualification of
     the Offered Securities for offering and sale under the applicable state
     securities or blue sky laws and real estate syndication laws of such
     jurisdictions as CSFBC designates and will continue such registration or
     qualifications in effect for as long as may be necessary to complete the
     distribution of the Offered Securities and to file such consents to service
     of process or other documents as may be necessary in order to effect such
     registration or qualification; provided, however, that in connection
     therewith the Company shall not be required to qualify as a foreign
     corporation or to execute a general consent to service of process in any
     jurisdiction.

          (h) During the period of five years hereafter, upon request of the
     Representatives, the Company will furnish to the Representatives and, upon
     request, to each of the other Underwriters, as soon as practicable after
     the end of each fiscal year, a copy of its annual report to shareholders
     for such year; and the Company will furnish to the Representatives (i) as
     soon as available, a copy of each report and any definitive proxy statement
     of the Company filed with the Commission under the Exchange Act or mailed
     to shareholders, and (ii) from time to time, such other information
     concerning the Company as CSFBC may reasonably request.

          (i) For a period of 90 days after the date of the date of the
     Prospectus, the Company will not offer, sell, contract to sell, pledge or
     otherwise dispose of, directly or indirectly, or, except for any
     Registration Statement on Form S-3 required to be filed by the Company
     during such 90 day period pursuant to the Company Registration Rights
     Agreements, file with the Commission a registration statement under the Act
     relating to, any additional shares of its Securities or securities
     convertible into or exchangeable or exercisable for any shares of its
     Securities, or publicly disclose the intention to make any such offer,
     sale, pledge, disposition or filing, without the prior written consent of
     CSFBC, except issuances of Securities pursuant to the conversion or
     exchange of convertible or exchangeable securities or the exercise of
     warrants or options, in each case outstanding on the date hereof, grants of
     employee stock options pursuant to the terms of a plan in effect on the
     date hereof, issuances of Securities pursuant to the exercise of such
     options or issuances of restricted securities constituting either common or
     preferred units of the Company's operating partnership in acquisition
     transactions.

          (j) Intentionally Omitted.


                                       16



          (k) The Company will pay all costs, fees, taxes and expenses incident
     to the performance of its obligations under this Agreement, whether or not
     the transactions contemplated herein are consummated or this Agreement is
     terminated, including all costs, fees, taxes and expenses incident to (i)
     the printing, filing or other production of documents with respect to the
     transactions, including any costs of printing the Registration Statements
     originally filed with respect to the Offered Securities and any amendment
     thereto, any Rule 462(b) Registration Statement and the Prospectus and any
     amendment or supplement thereto, this Agreement and any blue sky memoranda,
     (ii) all arrangements relating to the mailing and delivery to the
     Underwriters of copies of the foregoing documents, (iii) the fees, expenses
     and disbursements of the counsel, accountants and any other experts or
     advisors retained by the Company and the Selling Shareholder, (iv)
     preparation, printing, issuance and delivery to the Underwriters of any
     certificates evidencing the Offered Securities, including transfer agent's
     and registrar's fees, (v) the registration or qualification of the Offered
     Securities under state securities and blue sky laws and the real estate
     syndication laws of the several states, including filing fees and fees and
     disbursements of counsel for the Underwriters relating thereto, (vi) the
     filing fees and disbursement of counsel for the Underwriters solely in
     connection with the review and clearance of the offering of the Offered
     Securities by the NASD relating to the Offered Securities, (vii) the
     listing of the Offered Securities on the NYSE, (viii) meetings with
     prospective investors in the Offered Securities (other than shall have been
     specifically approved by the Representatives to be paid for by the
     Underwriters), (ix) advertising approved by the Company relating to the
     offering of the Offered Securities (other than shall have been specifically
     approved by the Representatives to be paid for by the Underwriters) and (x)
     any transfer taxes imposed on the sale by the Company and the Selling
     Shareholder of the Offered Securities to the Underwriters. If the sale of
     the Offered Securities provided for herein is not consummated because any
     condition to the obligations of the Underwriters set forth in Section 6
     hereof is not satisfied, because this Agreement is terminated or because of
     any failure, refusal or inability on the part of the Company or the
     Operating Partnership to perform all obligations and satisfy all conditions
     on its part to be performed or satisfied hereunder other than by reason of
     a default by any of the Underwriters, the Company and the Operating
     Partnership will reimburse the Underwriters severally upon demand for all
     out-of-pocket expenses (including fees and disbursements of counsel) that
     are the responsibility of the Company pursuant to this Section 5(k) and
     that shall have been incurred by them in connection with the proposed
     purchase and sale of the Offered Securities. If the sale of the Offered
     Securities provided for herein is not consummated because any condition to
     the obligations of the Underwriters set forth in Section 6 hereof relating
     to the Selling Shareholder is not satisfied or because of any failure,
     refusal or inability on the part of the Selling Shareholder to perform all
     obligations and satisfy all conditions on its part to be performed or
     satisfied hereunder other than by reason of a default by any of the
     Underwriters, the Selling Shareholder will reimburse the Underwriters
     severally upon demand for all out of pocket expenses (including fees and
     disbursements of counsel) that would be the responsibility of the Company
     pursuant to this Section 5(k) and that shall have been incurred by them in
     connection with the proposed purchase and sale of the Offered Securities.
     The Company, the Operating Partnership and the Selling Shareholder shall
     not in any event be liable to any of the Underwriters for the loss of
     anticipated profits from the transactions covered by this Agreement.

          (l) The Company will apply the net proceeds from the sale of its
     Offered Securities as set forth under "USE OF PROCEEDS" in the Prospectus.

          (m) The Company will not, at any time, directly or indirectly, (i)
     take any action designed to cause or to result in, or that has constituted
     or which might reasonably be expected to constitute, the stabilization or
     manipulation of the price of any security of the Company to facilitate the
     sale or resale of the Offered Securities or (ii) (A) sell, bid for,
     purchase, or pay


                                       17


     anyone any compensation for soliciting purchases of, the Offered Securities
     or (B) pay or agree to pay to any person any compensation for soliciting
     another to purchase any other securities of the Company.

          (n) If at any time during the period prior to the Optional Closing
     Date, any rumor, publication or event relating to or affecting the Company
     shall occur as a result of which in your opinion the market price of the
     Offered Securities has been or is likely to be materially affected
     (regardless of whether such rumor, publication or event necessitates a
     supplement to or amendment of the Prospectus), the Company will, after
     notice from you advising the Company to the effect set forth above,
     forthwith prepare, consult with you concerning the substance of, and
     disseminate a press release or other public statement, reasonably
     satisfactory to you, responding to or commenting on such rumor, publication
     or event.

          (o) If the Company elects to rely on Rule 462(b), the Company shall
     both file a Rule 462(b) Registration Statement with the Commission in
     compliance with Rule 462(b) and pay the applicable fees or give irrevocable
     instructions for the payment of such fees in accordance with Rule 111
     promulgated under the Act by the earlier of (i) 10:00 A.M. Eastern time on
     the date following the date of this Agreement and (ii) the time
     confirmations are sent or given, as specified by Rule 462(b)(2).

          (p) The Company will use its best efforts to cause the Offered
     Securities to be duly authorized for listing by the NYSE prior to the First
     Closing Date and to maintain the listing of the Offered Securities on the
     NYSE for a period of two years after the First Closing Date and thereafter
     unless the Company's Board of Trustees determines that it is no longer in
     the best interests of the Company for the Offered Securities to continue to
     be so listed.

          (q) During the period when the Prospectus is required to be delivered
     under the Act or the Exchange Act in connection with sales of the Offered
     Securities, to file all documents required to be filed by it with the
     Commission pursuant to Section 13, 14 or 15 of the Exchange Act within the
     time periods required by the Exchange Act.

          (r) The Company will use its best efforts to continue to qualify as a
     REIT under Sections 856 through 860 of the Code unless the Company's Board
     of Trustees determines that it is no longer in the best interests of the
     Company to be so qualified.

          (s) Each certificate signed by any officer or authorized
     representative of the Company or any Subsidiary and delivered to the
     Representatives or counsel for the Underwriters shall be deemed to be a
     representation and warranty by the Company or any Subsidiary to each
     Underwriter as to the matters covered thereby.

     6. CONDITIONS OF THE OBLIGATIONS OF THE UNDERWRITERS. The obligations of
the several Underwriters to purchase and pay for the Firm Securities under this
Agreement shall be subject, in the Representatives' sole discretion, to the
satisfaction of each of the following conditions:

          (a) All the representations and warranties of the Company, the
     Operating Partnership and the Selling Shareholder contained in this
     Agreement and all certificates of officers of the Company, the Operating
     Partnership and the Selling Shareholder made or delivered pursuant to this
     Agreement shall be true and correct, in all material respects, on the First
     Closing Date with the same force and effect as if made on and as of the
     First Closing Date.


                                       18


          (b) The Registration Statements, including any Rule 462(b)
     Registration Statement, has become effective under the Act; the Prospectus
     and any amendment or supplement thereto, shall have been filed with the
     Commission pursuant to Rule 424(b) within the applicable time period
     prescribed for such filing by such Rule; if the Company is required to file
     a Rule 462(b) Registration Statement after the effectiveness of this
     Agreement, such Rule 462(b) Registration Statement shall have been filed by
     10:00 A.M., New York City time, on the day after the date of this
     Agreement; and no stop order suspending the effectiveness of the
     Registration Statements or any post-effective amendment thereto and no
     order directed at any document incorporated by reference in the
     Registration Statements or the Prospectus or any amendment or supplement
     thereto shall have been issued, and no proceedings for that purpose shall
     have been instituted or threatened, or, to the knowledge of the Company or
     the Selling Shareholder, after due inquiry, shall be contemplated by the
     Commission. No stop order suspending the effectiveness of the Registration
     Statements or any post-effective amendment thereto and no order directed at
     any document incorporated by reference in the Registration Statements or
     the Prospectus or any amendment or supplement thereto shall have been
     issued, and no proceedings for that purpose shall have been instituted or
     threatened, or, to the knowledge of the Company, after due inquiry, shall
     be contemplated by the state securities authority of any jurisdiction.

          (c) Subsequent to the execution and delivery of this Agreement, there
     shall not have occurred (i) any change, or any development or event
     involving a prospective change, in the condition (financial or other),
     business, properties or results of operations of the Company and its
     Subsidiaries taken as one enterprise which, in the judgment of a majority
     in interest of the Underwriters including the Representatives, is material
     and adverse and makes it impractical or inadvisable to proceed with
     completion of the public offering or the sale of and payment for the
     Offered Securities; (ii) any downgrading in the rating of any debt
     securities or preferred stock of the Company by any "NATIONALLY RECOGNIZED
     STATISTICAL RATING ORGANIZATION" (as defined for purposes of Rule 436(g)
     under the Act), or any public announcement that any such organization has
     under surveillance or review its rating of any debt securities or preferred
     stock of the Company (other than an announcement with positive implications
     of a possible upgrading, and no implication of a possible downgrading, of
     such rating) or any announcement that the Company has been placed on
     negative outlook; (iii) any material suspension or material limitation of
     trading in securities generally on the NYSE, or any setting of minimum
     prices for trading on such exchange, or any suspension of trading of any
     securities of the Company on any exchange or in the over-the-counter
     market; (iv) any banking moratorium declared by U.S. Federal or New York
     authorities; or (v) any outbreak or escalation of major hostilities in
     which the United States is involved, any declaration of war by Congress or
     any other substantial national or international calamity or emergency if,
     in the judgment of a majority in interest of the Underwriters including the
     Representatives, the effect of any such outbreak, escalation, declaration,
     calamity or emergency makes it impractical or inadvisable to proceed with
     completion of the public offering or the sale of and payment for the
     Offered Securities.

          (d) The Representatives shall have received an opinion (satisfactory
     to you and your counsel), dated the First Closing Date, of Morgan, Lewis &
     Bockius LLP, counsel for the Company, to the effect that:

               (i) The Company and each of the Subsidiaries are validly existing
          as corporations, limited partnerships, real estate investment trusts
          or limited liability companies, as the case may be, in good standing
          under the laws of their respective jurisdictions of formation and are
          duly qualified to transact business as foreign corporations, limited
          partnerships, real estate investment trusts or limited liability
          companies, as the case may be, and are in good standing under the laws
          of the respective


                                       19


          jurisdictions identified on Schedule II hereto where the ownership or
          leasing of their respective properties or the conduct of their
          respective businesses requires such qualification, except where the
          failure to be so qualified would not have a Material Adverse Effect;

               (ii) The Company and each of the Subsidiaries have trust,
          corporate or partnership authority or power, whichever is appropriate,
          to own, operate or lease their respective properties and other assets
          and conduct the respective businesses in which they are engaged or
          propose to engage, in each case, as described in the Registration
          Statements and the Prospectus, and the Company and the Operating
          Partnership have trust or partnership power, as the case may be, to
          enter into this Agreement and to carry out all the terms and
          provisions hereof to be carried out by them;

               (iii) The Company has an authorized capitalization consisting of
          55,000,000 shares of beneficial interest as set forth in the
          Prospectus; the Offered Securities to be sold by the Company have been
          duly authorized for issuance and sale to the Underwriters pursuant to
          this Agreement by all necessary action of the Company and, when
          validly issued and delivered to and paid for by the Underwriters
          pursuant to this Agreement and in accordance with the resolutions of
          the Board of Trustees of the Company authorizing their issuance, will
          be duly authorized, validly issued, fully paid and nonassessable; no
          holders of outstanding shares of beneficial interest of the Company
          are entitled, to such counsel's knowledge, to any preemptive or other
          rights to subscribe for any of the Offered Securities; the terms of
          the Offered Securities conform in all material respects to the
          statements and descriptions related thereto under the captions
          "DESCRIPTION OF SHARES" contained in the Prospectus. The form of share
          certificate evidencing the Offered Securities is in due and proper
          form in all material respects and complies in all material respects
          with all applicable legal requirements under Maryland law. The
          issuance of the Offered Securities is not subject to any preemptive or
          other similar rights arising under Title 8 of the Corporations and
          Associations Article of the Annotated Code of Maryland or the
          Company's declaration of trust or bylaws, as amended to date;

               (iv) The statements set forth under the heading "DESCRIPTION OF
          SHARES" in the Prospectus, insofar as such statements purport to
          summarize certain provisions of the Offered Securities and the
          Declaration of Trust and bylaws of the Company and the Certificate of
          Limited Partnership of the Operating Partnership, have been reviewed
          by such counsel and are correct in all material respects and provide a
          fair summary of such provisions; and the statements set forth under
          the heading "CERTAIN FEDERAL INCOME TAX MATTERS" and "DESCRIPTION OF
          SHARES" in the Prospectus, insofar as such statements constitute
          statements of law, description of statutes, rules or regulations, a
          summary of the legal matters or proposed legislation referred to
          therein, have been reviewed by such counsel and are correct in all
          material respects and provide a fair summary of such matters, except
          that as to the authorization, valid issuance, full payment and
          non-assessability, such counsel's opinion is applicable only to those
          Offered Securities sold by the Company;

               (v) The execution and delivery of this Agreement has been duly
          authorized by all necessary action of the Company and the Operating
          Partnership and this Agreement has been duly executed and delivered by
          the Company and the Operating Partnership;


                                       20


               (vi) To such counsel's knowledge, no legal or governmental
          proceedings are pending to which the Company or any of the
          Subsidiaries is a party or to which the property of the Company or any
          of the Subsidiaries is subject that are required to be described in
          the Registration Statements or the Prospectus and are not described
          therein, and, to the extent described therein, the descriptions
          thereof are accurate in all material respects and, to the knowledge of
          such counsel, no such proceedings have been threatened against the
          Company or any of the Subsidiaries or with respect to any of their
          respective properties; and to such counsel's knowledge no contract,
          statute, regulation or other document is required to be described in
          the Registration Statements or the Prospectus or to be filed as an
          exhibit to the Registration Statements that is not described therein
          or filed as an exhibit thereto;

               (vii) To such counsel's knowledge, the issuance, offering and
          sale of the Offered Securities to the Underwriters by the Company
          pursuant to this Agreement, the execution, delivery and performance
          and the compliance with this Agreement by the Company and the
          Operating Partnership and the consummation by the Company and the
          Operating Partnership of the other transactions herein contemplated do
          not and will not (A) require the consent, approval, authorization,
          registration, order, filing or qualification of or with any court,
          regulatory body, administrative agency or other governmental
          authority, except such as have been obtained and such as may be
          required under state securities or blue sky laws or real estate
          syndication laws of the various states in connection with the purchase
          and distribution of the securities by the Underwriters, or as may be
          required under the Act or other securities laws or bylaws and rules of
          the NASD, or the listing requirements of the NYSE or such as have been
          received prior to the date of the opinion, or (B) conflict with or
          result in a breach or violation of any of the terms and provisions of,
          or constitute a default under, whether with or without the giving of
          notice or passage of time or both, (x) the declaration of trust and
          bylaws of the Company, the charter and bylaws of each Subsidiary that
          is a corporation, the partnership agreement of each Subsidiary that is
          a partnership or the operating agreement of each Subsidiary that is a
          limited liability company, (y) any document (as in effect on the date
          of such opinion) listed on Schedule III (it being understood that such
          counsel may assume compliance with the financial covenants contained
          in any such document), (C) violate or conflict with any applicable
          law, rule or administrative regulation of the United States, the
          General Corporation Law or Revised Uniform Limited Partnership Act of
          the State of Delaware or Title 8 of the Corporations and Associations
          Article of the Annotated Code of the State of Maryland, or (D) violate
          any order or administrative or court decree of which such counsel is
          aware, except in each case (other than for Sections 6(d)(viii)(B)(x)
          and 6(d)(viii)(B)(y) above) for requirements, conflicts, breaches,
          violations or defaults that in the aggregate would not have a Material
          Adverse Effect;

               (viii) The Registration Statements are effective under the Act;
          the Prospectus has been filed with the Commission in the manner and
          within the time period required by Rule 424(b) under the Act; and,
          based solely on the oral advisement of a member of the Commission's
          staff, no stop order suspending the effectiveness of the Registration
          Statements or any post-effective amendment thereto has been issued,
          and no proceedings for that purpose have been instituted or, to the
          knowledge of such counsel, are threatened or contemplated by the
          Commission;

               (ix) The documents filed pursuant to the Exchange Act and
          incorporated by reference in the Prospectus (other than the financial
          statements and related schedules, other financial information and
          statistical data derived from such financial statements,


                                       21


          schedules and other financial data contained therein, as to which
          counsel need express no opinion), when they were filed with the
          Commission, complied as to form in all material respects with the
          applicable requirements of the Exchange Act;

               (x) The Registration Statements and any Rule 462(b) Registration
          Statement, in each case together with the Prospectus and each
          amendment and supplement thereto, as of the issue date of such
          Prospectus (including, but only as of their respective filing dates,
          the documents incorporated by reference therein but not including the
          financial statements and related schedules, other financial
          information and statistical data derived from such financial
          statements, schedules and other financial data contained therein, as
          to which such counsel need express no opinion) complied as to form in
          all material respects with the applicable requirements of the Act;

               (xi) The authorized shares of beneficial interest of the Company
          conform as to legal matters in all material respects to the
          description thereof contained in the Prospectus;

               (xii) The Company and the Subsidiaries are not and, after giving
          effect to the offering and sale of the Offered Securities and the
          application of the proceeds thereof as described in the Prospectus,
          will not be required to be registered as an "INVESTMENT COMPANY" under
          the Investment Company Act of 1940, as amended; and

               (xiii) To such counsel's knowledge, except for the Company
          Registration Rights Agreements, there are no contracts or agreements
          between the Company and any person granting such person the right to
          require the Company to include securities of the Company held by such
          person with the Offered Securities registered pursuant to the
          Registration Statement.

          In addition, Morgan, Lewis & Bockius LLP shall confirm that the
     opinion filed as Exhibit 8.1 to the Registration Statements is true and
     correct as of the date thereof and permit the Underwriters to rely on such
     opinion as if it were addressed to the Underwriters. Also, if the NYSE has
     approved and authorized the listing of the Offered Securities as of the
     Closing Date, Morgan, Lewis & Bockius LLP shall confirm that the Offered
     Securities have been duly authorized for listing, subject to official
     notice of issuance, on the NYSE.

          Further, Morgan, Lewis & Bockius LLP shall state that they have
     participated in conferences with officers and other representatives of the
     Company and the Subsidiaries, representatives of the independent public
     accountants for the Company and representatives of the Underwriters and
     their counsel at which the contents of the Registration Statements and the
     Prospectus and related matters were discussed. On the basis thereof
     (relying as to materiality to the extent it deems appropriate upon the
     opinions of officers and other representatives of the Company), but without
     independent verification by such counsel of, and without passing upon or
     assuming any responsibility for, the accuracy, completeness or fairness of
     the statements contained in the Registration Statements or the Prospectus
     or any amendments or supplements thereto, no facts have come to the
     attention of such counsel that lead them to believe that (i) the
     Registration Statements, at the time such Registration Statements became
     effective, contained any untrue statement of a material fact or omitted to
     state any material fact required to be stated therein or necessary in order
     to make the statements therein not misleading or (ii) the Prospectus, as of
     its date or at the First Closing Date contained or contains any untrue
     statement of a material fact or omitted or omits to state a material fact
     necessary to make the statements therein, in the light of the circumstances
     under which they were made, not misleading (it being understood that


                                       22


     such counsel need express no opinion with respect to the financial
     statements and related schedules and other financial and statistical data
     derived from such financial statements included in the Registration
     Statements or the Prospectus).

          In giving its opinion, such counsel shall expressly limit their
     opinion to matters of Federal and Pennsylvania law and the Revised Uniform
     Limited Partnership Act of the State of Delaware, the General Corporation
     Law of the State of Delaware and Title 8 of the Corporations and
     Associations Article of the Annotated Code of Maryland and may rely without
     independent verification (A) as to all matters of fact, upon certificates
     and statements of officers, trustees, directors, partners and employees of
     and accountants for the Company and the Subsidiaries and (B) as to the good
     standing and qualification of the Company and the Subsidiaries to do
     business in any state or jurisdiction, upon certificates of appropriate
     government officials or opinions of counsel in such jurisdictions. Counsel
     need express no opinion (i) as to the enforceability of forum selection
     clauses or (ii) with respect to the requirements of, or compliance with,
     any state securities or blue sky or real estate syndication laws.

          For the purposes of the opinions presented in this Section 6(d), the
     term "SUBSIDIARIES" shall include only those subsidiaries that are listed
     on Schedule IV. References to the Registration Statements and the
     Prospectus in this paragraph (d) shall include any amendment or supplement
     thereto at the date of such opinion.

          (e) You shall have received on the First Closing Date an opinion or
     opinions (satisfactory to you and your counsel), dated the First Closing
     Date, of John H. Gurley, Esq., General Counsel to the Company, as to the
     following matters:

               (i) The Company and each of the Subsidiaries are validly existing
          as corporations, limited partnerships, real estate investment trusts
          or limited liability companies, as the case may be, in good standing
          under the laws of their respective jurisdictions of formation and are
          duly qualified and registered to transact business as foreign
          corporations, limited partnerships, real estate investment trusts or
          limited liability companies, as the case may be, and are in good
          standing under the laws of the respective jurisdictions identified on
          Schedule II hereto where the ownership or leasing of their respective
          properties or the conduct of their respective businesses requires such
          qualification, except where the failure to be so qualified would not
          have a Material Adverse Effect;

               (ii) The Company and each of the Subsidiaries have trust,
          corporate or partnership authority or power, whichever is appropriate,
          to own, operate or lease their respective properties and other assets
          and conduct the respective businesses in which they are engaged or
          propose to engage, in each case, as described in the Registration
          Statement and the Prospectus, and the Company and the Operating
          Partnership have trust or partnership power, as the case may be, to
          enter into this Agreement and to carry out all the terms and
          provisions hereof to be carried out by them;

               (iii) The issued and outstanding common and preferred units of
          limited partnership of the Operating Partnership, the issued and
          outstanding in the Company, and the issued and outstanding membership
          interests and other equity interests, as the case may be, of each of
          the other Subsidiaries have been duly authorized and validly issued,
          are, with respect to corporate Subsidiaries, as applicable, fully paid
          and nonassessable, have been issued in compliance with all applicable
          federal and state securities laws and, to the knowledge of such
          counsel, were not issued in violation of or subject to any


                                       23


          preemptive rights or other rights to subscribe for or purchase
          securities and, except as otherwise set forth in the Prospectus, to
          the knowledge of such counsel, are owned beneficially by the Company
          free and clear of any perfected security interests or, any other
          security interests, liens, encumbrances, equities or claims, except
          for security interests, liens, encumbrances, equities or claims
          pursuant to the terms of a bona fide financing transaction;

               (iv) To such counsel's knowledge, no legal or governmental
          proceedings are pending to which the Company or any of the
          Subsidiaries is a party or to which the property of the Company or any
          of the Subsidiaries is subject that are required to be described in
          the Registration Statements or the Prospectus and are not described
          therein, and the descriptions thereof are accurate in all material
          respects and, to the knowledge of such counsel, no such proceedings
          have been threatened against the Company or any of the Subsidiaries or
          with respect to any of their respective properties; and to such
          counsel's knowledge no contract, statute, regulation or other document
          is required to be described in the Registration Statements or the
          Prospectus or to be filed as an exhibit to the Registration Statements
          that is not described therein or filed as required and the
          descriptions of any such contracts, statutes, regulations or other
          documents are accurate in all material respects;

               (v) To such counsel's knowledge, the issuance, offering and sale
          of the Offered Securities to the Underwriters by the Company pursuant
          to this Agreement, the execution, delivery and performance and the
          compliance with this Agreement by the Company and the Operating
          Partnership and the consummation by the Company and the Operating
          Partnership of the other transactions herein contemplated do not and
          will not (A) require the consent, approval, authorization,
          registration, order, filing or qualification of or with any court,
          regulatory body, administrative agency or other governmental
          authority, except such as have been obtained and such as may be
          required under state securities or blue sky laws or real estate
          syndication laws of the various states in connection with the purchase
          and distribution of the securities by the Underwriters, or as may be
          required under the Act or other securities laws or bylaws and rules of
          the NASD, or the listing requirements of the NYSE or such as have been
          received prior to the date of the opinion, or (B) conflict with or
          result in a breach or violation of any of the terms and provisions of,
          or constitute a default under (whether with or without the giving of
          notice or passage of time or both), (x) the declaration of trust and
          bylaws of the Company, the charter and bylaws of each Subsidiary that
          is a corporation, the partnership agreement of each Subsidiary that is
          a partnership or the operating agreement of each Subsidiary that is a
          limited liability company, (y) any document (as in effect on the date
          of such opinion) listed on Schedule III (it being understood that such
          counsel may assume compliance with the financial covenants contained
          in any such document), (C) violate or conflict with any applicable
          law, rule or administrative regulation of the United States, the
          General Corporation Law or Revised Uniform Limited Partnership Act of
          the State of Delaware or Title 8 of the Corporations and Associations
          Article of the Annotated Code of the State of Maryland, or (D) violate
          any order or administrative or court decree of which such counsel is
          aware, except in each case (other than for Sections 6(d)(viii)(B)(x)
          and 6(d)(viii)(B)(y) above) for requirements, conflicts, breaches,
          violations or defaults that in the aggregate would not have a Material
          Adverse Effect; and

               (vi) To the knowledge of such counsel, neither the Company nor
          any of the Subsidiaries is in violation of its respective charter,
          declaration of trust, bylaws, partnership agreement or other
          organizational document, as the case may be, and, to such


                                       24


          counsel's knowledge, neither the Company nor any of such Subsidiaries
          is in default in the performance or observance of (and there is no
          event which, with or without the passage of time or the giving of
          notice, or both, would constitute a default under any of the
          foregoing), any obligation, agreement, covenant or condition contained
          in any document (as in effect on the date of such opinion) listed on
          Schedule III to which the Company or any of such Subsidiaries is a
          party or by which the Company or any of such Subsidiaries or their
          respective property is bound (it being understood that such counsel
          may assume compliance with the financial covenants contained in any
          such document), except in each case for violations or defaults which
          in the aggregate are not reasonably expected to have a Material
          Adverse Effect.

          In addition, John H. Gurley shall make statements similar to those
     contained in the second paragraph following Section 6(d)(xiii) hereto and
     shall be entitled to limit his opinions to those jurisdictions, qualify his
     opinion as, and rely on those persons described in the third paragraph
     following Section 6(d)(xiii) described therein. For the purposes of the
     opinions presented in this Section 6(e), the term "SUBSIDIARIES" shall
     include only those subsidiaries that are listed on Schedule V.

          (f) The Representative shall have received an opinion, dated the First
     Closing Date, of Sally Samuel, in-house counsel for the Selling
     Shareholder, to the effect that:

               (i) The Selling Shareholder had valid and unencumbered title to
          the Offered Securities delivered by the Selling Shareholder on such
          Closing Date and had full right, power and authority to sell, assign,
          transfer and deliver the Offered Securities delivered by the Selling
          Shareholder on such Closing Date hereunder; and, assuming that the
          Underwriters acquire the Offered Securities in accordance with the
          terms of this Agreement, the several Underwriters have acquired valid
          and unencumbered title to the Offered Securities purchased by them
          from the Selling Shareholder on such Closing Date hereunder;

               (ii) To such counsel's knowledge, no consent, approval,
          authorization or order of, or filing with, any governmental agency or
          body or any court is required to be obtained or made by the Selling
          Shareholder for the consummation of the transactions contemplated by
          this Agreement in connection with the sale of the Offered Securities
          sold by the Selling Shareholder, except such as have been obtained and
          made under the Act and such as may be required under state securities
          laws;

               (iii) To such counsel's knowledge, the execution, delivery and
          performance of this Agreement and the consummation of the transactions
          herein contemplated will not result in a breach or violation of any of
          the terms and provisions of, or constitute a default under, any
          statute, any rule, regulation or order of any governmental agency or
          body or any court having jurisdiction over the Selling Shareholder or
          any of its properties or any agreement or instrument to which the
          Selling Shareholder is a party or by which the Selling Shareholder is
          bound or to which any of the properties of the Selling Shareholder is
          subject, or the charter or by-laws of the Selling Shareholder which is
          a corporation;

               (iv) This Agreement has been duly authorized, executed and
          delivered by the Selling Shareholder;

               (v) The Selling Shareholder is a corporation duly organized,
          validly existing and in good standing as a corporation under the laws
          of the State of Maryland; and

                                       25


          In addition, Sally Samuel shall be entitled to limit her opinions to
     the laws of the State of Maryland, qualify her opinion as, and rely on
     those persons described in the third paragraph following Section 6(d)(xiii)
     described therein.

          (g) You shall have received on the First Closing Date an opinion,
     dated the First Closing Date, of Clifford Chance Rogers & Wells LLP,
     counsel for the Underwriters, as to the matters referred to in clauses
     (iii) (with respect to the second and fourth clauses only), (iv) (with
     respect to "DESCRIPTION OF SHARES" only), (v) and (xi) of Section 6(d) and
     in addition, Clifford Chance Rogers & Wells LLP shall make statements
     similar to those contained in the second and third paragraphs following
     Section 6(d)(xiv) hereto (with respect to Federal, New York, Delaware and
     Maryland laws only) and shall be entitled to rely on those persons
     described in the third paragraph following Section 6(d)(xiv) described
     therein.

          (h) You shall have received, on each of the date hereof and the First
     Closing Date, a letter dated the date hereof or the First Closing Date, as
     the case may be, in form and substance satisfactory to you (and your
     counsel), from PricewaterhouseCoopers LLP, independent public accountants,
     confirming that they are independent public accountants with respect to the
     Company and the Subsidiaries within the meaning of the Act and the
     applicable published rules and regulations thereunder and with respect to
     the financial and other statistical and numerical information contained in
     the Registration Statements and containing the information and statements
     of the type ordinarily included in accountants' "COMFORT LETTERS" to
     Underwriters with respect to the financial statements and certain financial
     information contained in the Registration Statements and the Prospectus.

          At the First Closing Date, PricewaterhouseCoopers LLP shall have
     furnished to the Underwriters a letter, dated the date of its delivery,
     which shall confirm, on the basis of a review in accordance with the
     procedures set forth in the letter from it, that nothing has come to its
     attention during the period from the date of the letter referred to in the
     prior sentence to a date (specified in the letter) not more than five days
     prior to the First Closing Date which would require any change in its
     letter dated the date hereof if it were required to be dated and delivered
     at the First Closing Date as the case may be.

          References to the Registration Statements and the Prospectus in this
     paragraph (h) with respect to either letter referred to above shall include
     any amendment or supplement thereto at the date of such letter.

          (i) The Company and the Subsidiaries shall not have failed on or prior
     to the First Closing Date to perform or comply with any of the agreements
     herein contained and required to be performed or complied with by the
     Company on or prior to the First Closing Date.

          (j) The Representatives shall have received a certificate, dated the
     First Closing Date, of Clay W. Hamlin, III and Roger A. Waesche, Jr.,
     solely in their capacities as the Chief Executive Officer and Chief
     Financial Officer of the Company to the effect that:

               (i) All the representations and warranties of the Company in this
          Agreement shall be true and correct, in all material respects, on the
          First Closing Date with the same force and effect as if made on and as
          of the First Closing Date. The Company has complied with all
          agreements and all conditions on its part to be performed or satisfied
          hereunder at or prior to the First Closing Date.

                                       26


               (ii) The Registration Statements, including any Rule 462(b)
          Registration Statement, has become effective under the Act; the
          Prospectus has been filed with the Commission pursuant to Rule 424(b)
          within the applicable time period prescribed for such filing by such
          Rule; no stop order suspending the effectiveness of the Registration
          Statements or any post-effective amendment thereto and no order
          directed at any document incorporated by reference in the Registration
          Statements or the Prospectus or any amendment or supplement thereto
          has been issued, and no proceedings for that purpose have been
          instituted or are pending before, or threatened or, to the best of the
          Company's knowledge, after due inquiry, are contemplated by the
          Commission; no stop order suspending the effectiveness of the
          Registration Statements or any post-effective amendment thereto and no
          order directed at any document incorporated by reference in the
          Registration Statements or the Prospectus or any amendment or
          supplement thereto has been issued, and no proceedings for that
          purpose have been instituted or are pending before, or threatened or,
          to the best of the Company's knowledge, after due inquiry, are
          contemplated by the state securities authority of any jurisdiction;
          and

               (iii) Subsequent to the respective dates as of which information
          is given in the Registration Statements and the Prospectus other than
          as set forth in or contemplated by the Registration Statements and the
          Prospectus (exclusive of any amendments or supplements thereto
          subsequent to the date of this Agreement) and prior to the First
          Closing Date, except for changes of a general nature applicable to all
          real estate investment trusts investing in commercial office
          properties, (i) there has not occurred any material adverse change or,
          to the best knowledge of such persons, any development involving a
          prospective material adverse change in the condition, financial or
          otherwise, or the results of operations, business, prospects,
          management or operations of the Company and the Subsidiaries, taken as
          a whole, (ii) there has been no casualty loss or condemnation or other
          adverse event with respect to any of the properties which would be
          material to the Company and the Subsidiaries, taken as a whole, (iii)
          there has not been any material adverse change or any development
          involving a prospective material adverse change in the capitalization,
          long-term or short-term debt or in the shares of beneficial interest
          or equity of the Company or any of the Subsidiaries, (iv) except as
          described in the Prospectus, neither the Company nor any of the
          Subsidiaries has incurred any material liability or obligation, direct
          or contingent, which would be material, nor have they entered into any
          transactions, other than pursuant to this Agreement and the
          transactions referred to herein or as contemplated in the Prospectus,
          which would be material, to the Company and its Subsidiaries taken as
          a whole, and (v) except for regular quarterly distributions on the
          Offered Securities and other securities issued by the Company, the
          Company has not paid or declared and will not pay or declare any
          dividends or other distributions of any kind on any class of its
          shares of beneficial interest except in the ordinary course of
          business consistent with such practice.

          (k) The Representatives shall have received a certificate, dated the
     First Closing Date, of Steven Kesler, solely in his capacity as the
     President of the Selling Shareholder to the effect that all the
     representations and warranties of the Selling Shareholder in this Agreement
     shall be true and correct, in all material respects, on the First Closing
     Date with the same force and effect as if made on and as of the First
     Closing Date, and that the Selling Shareholder has complied with all
     agreements and all conditions on its part to be performed or satisfied
     hereunder at or prior to the First Closing Date.

          (l) On or prior to the date of this Agreement, the Representatives
     shall have received lockup letters from each of the executive officers and
     trustees of the Company, whereby such


                                       27


     persons agree to, for a period of 90 days after the date of the initial
     public offering of the Offered Securities, not to offer, sell, contract to
     sell, pledge or otherwise dispose of, directly or indirectly, any
     additional shares of the Securities of the Company or securities
     convertible into or exchangeable or exercisable for any shares of
     Securities, enter into a transaction which would have the same effect, or
     enter into any swap, hedge or other arrangement that transfers, in whole or
     in part, any of the economic consequences of ownership of the Securities,
     whether any such aforementioned transaction is to be settled by delivery of
     the Securities or such other securities, in cash or otherwise, or publicly
     disclose the intention to make any such offer, sale, pledge or disposition,
     or enter into any such transaction, swap, hedge or other arrangement,
     without, in each case, the prior written consent of CSFBC.

          (m) On or before the First Closing Date, the Representatives and
     counsel for the Underwriters shall have received such further certificates,
     letters, documents, opinions or other information as they may have
     reasonably requested from the Company for the purpose of enabling them to
     pass upon the issuance and sale of the Offered Securities, as herein
     contemplated and related proceedings, or in order to evidence the accuracy
     of any of the representations or warranties, or the fulfillment of any of
     the conditions, herein contained; and all proceedings taken by the Company
     in connection with the issuance and sale of the Offered Securities as
     herein contemplated shall be reasonably satisfactory in form and substance
     to the Representatives and counsel for the Underwriters.

          (n) The Offered Securities shall have been approved for listing on the
     NYSE, subject to official notice of issuance.

     The respective obligations of the several Underwriters to purchase and pay
for any Optional Securities shall be subject, in their discretion, to each of
the foregoing conditions to purchase the Firm Securities (except that all
references to the Firm Securities and the First Closing Date shall be deemed to
refer to such Optional Securities and the related Optional Closing Date,
respectively), including, without limitation:

          (a) A certificate, dated such Optional Closing Date, of the President
     or a Vice President and the chief financial or chief accounting officer of
     the Company confirming that the certificates delivered at the First Closing
     Date pursuant to Section 6 hereof remain true and correct in all material
     respects as of such Optional Closing Date.

          (b) Intentionally omitted.

          (c) An opinion of Morgan, Lewis & Bockius LLP in form and substance
     satisfactory to you and your counsel, dated such Optional Closing Date,
     relating to the Optional Securities to be purchased on such Optional
     Closing Date and otherwise to the same effect as the opinion required by
     Section 6(d) hereof.

          (d) An opinion of John H. Gurley, Esq. in form and substance
     reasonably satisfactory to you and your counsel, dated such Optional
     Closing Date, relating to the Optional Securities to be purchased on such
     Optional Closing Date and otherwise to the same effect as the opinion
     required by Section 6(e) hereof.

          (e) Intentionally omitted.

          (f) An opinion of Clifford Chance Rogers & Wells LLP, counsel for the
     Underwriters, dated such Optional Closing Date, relating to the Optional
     Securities to be


                                       28


     purchased on such Optional Closing Date and otherwise to the same effect as
     the opinion required by Section 6(g) hereof.

          (g) A letter from PricewaterhouseCoopers LLP, in form and substance
     satisfactory to you and your counsel and dated such Optional Closing Date,
     substantially the same in form and substance as the letter furnished to the
     Underwriters pursuant to Section 6(h) hereof, dated not more than five days
     prior to such Optional Closing Date.

     7. INDEMNIFICATION AND CONTRIBUTION. (a) The Company and the Operating
Partnership will indemnify and hold harmless each Underwriter, its partners,
directors and officers and each person, if any, who controls such Underwriter
within the meaning of Section 15 of the Act, against any losses, claims, damages
or liabilities, joint or several, to which such Underwriter may become subject,
under the Act or otherwise, insofar as such losses, claims, damages or
liabilities (or actions in respect thereof) arise out of or are based upon any
untrue statement or alleged untrue statement of any material fact contained in
any Registration Statement, the Prospectus, or any amendment or supplement
thereto, or any related preliminary prospectus, or arise out of or are based
upon the omission or alleged omission to state therein a material fact required
to be stated therein or necessary to make the statements therein not misleading,
or arise out of any untrue statement or alleged untrue statement made by the
Company or the Operating Partnership in Section 2 of this Agreement, or arise
out of any untrue statement or alleged untrue statement of any material fact
contained in any application or other document, or any amendment or supplement
thereto, executed by the Company or the Operating Partnership or based upon
written information furnished by or on behalf of the Company or the Operating
Partnership filed in any jurisdiction in order to qualify the Offered Securities
under the securities or blue sky laws thereof or filed with the Commission or
any securities association or securities exchange, or arise out of any untrue
statement or alleged untrue statement of any material fact contained in any
audio or visual materials prepared by the Company or the Operating Partnership
or based upon written information furnished by or on behalf of the Company or
the Operating Partnership (including, without limitation, slides, videos, films,
tape recordings) used in connection with the marketing of the Offered
Securities, including, without limitation, statements communicated to securities
analysts employed by the Underwriters, and will reimburse each Underwriter for
any legal or other expenses reasonably incurred by such Underwriter in
connection with investigating or defending any such loss, claim, damage,
liability or action as such expenses are incurred; provided, however, that the
Company will not be liable in any such case to the extent that any such loss,
claim, damage or liability arises out of or is based upon an untrue statement or
alleged untrue statement in or omission or alleged omission from any of such
documents in reliance upon and in conformity with written information furnished
to the Company by any Underwriter through the Representatives specifically for
use therein, it being understood and agreed that the only such information
furnished by any Underwriter consists of the information described as such in
subsection (d) below.

     (b) The Selling Shareholder will indemnify and hold harmless each
Underwriter, its partners, directors and officers and each person who controls
such Underwriter within the meaning of Section 15 of the Act, against any
losses, claims, damages or liabilities, joint or several, to which such
Underwriter may become subject, under the Act or otherwise, insofar as such
losses, claims, damages or liabilities (or actions in respect thereof) arise out
of or are based upon any untrue statement or alleged untrue statement of any
material fact contained in any Registration Statement, the Prospectus, or any
amendment or supplement thereto, or any related preliminary prospectus, or arise
out of or are based upon the omission or alleged omission to state therein a
material fact required to be stated therein or necessary to make the statements
therein not misleading, and will reimburse each Underwriter for any legal or
other expenses reasonably incurred by such Underwriter in connection with
investigating or defending any such loss, claim, damage, liability or action as
such expenses are incurred; provided, however, that the Selling Shareholder will
not be liable in any such case to the extent that any such loss, claim, damage
or liability arises out of or is based upon an untrue statement or alleged
untrue statement in or omission or alleged


                                       29


omission from any of such documents in reliance upon and in conformity with
written information furnished to the Company by an Underwriter through the
Representatives specifically for use therein, it being understood and agreed
that the only such information furnished by any Underwriter consists of the
information described as such in subsection (d) below; provided, further, that
the Selling Shareholder shall only be subject to such liability to the extent
that the untrue statement or alleged untrue statement or omission or alleged
omission is based upon information provided by the Selling Shareholder or
contained in a representation or warranty given by the Selling Shareholder in
this Agreement.

     (c) Each Underwriter will severally and not jointly indemnify and hold
harmless the Company, its directors and officers and each person, if any who
controls the Company within the meaning of Section 15 of the Act and the Selling
Shareholder, its directors and officers and each person, if any, who controls
the Selling Shareholder within the meaning of Section 15 of the Act, against any
losses, claims, damages or liabilities to which the Company or the Selling
Shareholder may become subject, under the Act or otherwise, insofar as such
losses, claims, damages or liabilities (or actions in respect thereof) arise out
of or are based upon any untrue statement or alleged untrue statement of any
material fact contained in any Registration Statement, the Prospectus, or any
amendment or supplement thereto, or any related preliminary prospectus, or arise
out of or are based upon the omission or the alleged omission to state therein a
material fact required to be stated therein or necessary to make the statements
therein not misleading, in each case to the extent, but only to the extent, that
such untrue statement or alleged untrue statement or omission or alleged
omission was made in reliance upon and in conformity with written information
furnished to the Company by such Underwriter through the Representatives
specifically for use therein, and will reimburse any legal or other expenses
reasonably incurred by the Company and the Selling Shareholder in connection
with investigating or defending any such loss, claim, damage, liability or
action as such expenses are incurred, it being understood and agreed that the
only such information furnished by any Underwriter consists of the following
information in the Prospectus furnished on behalf of each Underwriter: the
information in the second and third sentences of the fourth paragraph under the
caption "UNDERWRITING," the information in the second and third sentences of the
seventh paragraph and the eighth, ninth and tenth paragraphs under the caption
"UNDERWRITING" and the statement regarding the affiliation of KeyCorp and
McDonald Investments, Inc. and the sixth and seventh sentences in the eleventh
paragraph.

     (d) Promptly after receipt by an indemnified party under this Section of
notice of the commencement of any action, such indemnified party will, if a
claim in respect thereof is to be made against the indemnifying party under
subsection (a), (b) or (c) above, notify the indemnifying party of the
commencement thereof; but the omission so to notify the indemnifying party will
not relieve it from any liability which it may have to any indemnified party
otherwise than under subsection (a), (b) or (c) above, except to the extent such
omission so to notify the indemnifying party materially prejudices the
indemnifying party. In case any such action is brought against any indemnified
party and it notifies the indemnifying party of the commencement thereof, the
indemnifying party will be entitled to participate therein and, to the extent
that it may wish, jointly with any other indemnifying party similarly notified,
to assume the defense thereof, with counsel satisfactory to such indemnified
party (who shall not, except with the consent of the indemnified party, be
counsel to the indemnifying party), and after notice from the indemnifying party
to such indemnified party of its election so to assume the defense thereof, the
indemnifying party will not be liable to such indemnified party under this
Section for any legal or other expenses subsequently incurred by such
indemnified party in connection with the defense thereof other than reasonable
costs of investigation. No indemnifying party shall, without the prior written
consent of the indemnified party, effect any settlement of any pending or
threatened action in respect of which any indemnified party is or could have
been a party and indemnity could have been sought hereunder by such indemnified
party unless such settlement (i) includes an unconditional release of such
indemnified party from all liability on any claims that are the subject matter
of such action and (ii) does not include a


                                       30


statement as to, or an admission of, fault, culpability or a failure to act by
or on behalf of an indemnified party.

     (e) If the indemnification provided for in this Section is unavailable or
insufficient to hold harmless an indemnified party under subsection (a), (b) or
(c) above, then each indemnifying party shall contribute to the amount paid or
payable by such indemnified party as a result of the losses, claims, damages or
liabilities referred to in subsection (a), (b) or (c) above (i) in such
proportion as is appropriate to reflect the relative benefits received by the
Company and the Selling Shareholder on the one hand and the Underwriters on the
other from the offering of the Offered Securities or (ii) if the allocation
provided by clause (i) above is not permitted by applicable law, in such
proportion as is appropriate to reflect not only the relative benefits referred
to in clause (i) above but also the relative fault of the Company and the
Selling Shareholder on the one hand and the Underwriters on the other in
connection with the statements or omissions which resulted in such losses,
claims, damages or liabilities as well as any other relevant equitable
considerations. The relative benefits received by the Company and the Selling
Shareholder on the one hand and the Underwriters on the other shall be deemed to
be in the same proportion as the total net proceeds from the offering (before
deducting expenses) received by the Company and the Selling Shareholder bear to
the total underwriting discounts and commissions received by the Underwriters.
The relative fault shall be determined by reference to, among other things,
whether the untrue or alleged untrue statement of a material fact or the
omission or alleged omission to state a material fact relates to information
supplied by the Company, the Selling Shareholder or the Underwriters and the
parties' relative intent, knowledge, access to information and opportunity to
correct or prevent such untrue statement or omission. The amount paid by an
indemnified party as a result of the losses, claims, damages or liabilities
referred to in the first sentence of this subsection (e) shall be deemed to
include any legal or other expenses reasonably incurred by such indemnified
party in connection with investigating or defending any action or claim which is
the subject of this subsection (e). Notwithstanding the provisions of this
subsection (e), no Underwriter shall be required to contribute any amount in
excess of the amount by which the total price at which the Offered Securities
underwritten by it and distributed to the public were offered to the public
exceeds the amount of any damages which such Underwriter has otherwise been
required to pay by reason of such untrue or alleged untrue statement or omission
or alleged omission. No person found by a court to be guilty of fraudulent
misrepresentation (within the meaning of Section 11(f) of the Act) shall be
entitled to contribution from any person who was not found by a court to be
guilty of such fraudulent misrepresentation. The Underwriters' obligations in
this subsection (e) to contribute are several in proportion to their respective
underwriting obligations and not joint.

     (f) The obligations of the Company and the Selling Shareholder under this
Section shall be in addition to any liability which the Company and the Selling
Shareholder may otherwise have and shall extend, upon the same terms and
conditions, to each person, if any, who controls any Underwriter within the
meaning of the Act; and the obligations of the Underwriters under this Section
shall be in addition to any liability which the respective Underwriters may
otherwise have and shall extend, upon the same terms and conditions, to each
director of the Company or the Selling Shareholder, as applicable, to each
officer of the Company who has signed a Registration Statement and to each
person, if any, who controls the Company or the Selling Shareholder, as
applicable, within the meaning of the Act.

     8. DEFAULT OF UNDERWRITERS. If any Underwriter or Underwriters default in
their obligations to purchase Offered Securities hereunder on either the First
or any Optional Closing Date and the aggregate number of shares of Offered
Securities that such defaulting Underwriter or Underwriters agreed but failed to
purchase does not exceed 10% of the total number of shares of Offered Securities
that the Underwriters are obligated to purchase on such Closing Date, CSFBC may
make arrangements satisfactory to the Company and the Selling Shareholder for
the purchase of such Offered Securities by other persons, including any of the
Underwriters, but if no such arrangements are made by such Closing


                                       31


Date, the non-defaulting Underwriters shall be obligated severally, in
proportion to their respective commitments hereunder, to purchase the Offered
Securities that such defaulting Underwriters agreed but failed to purchase on
such Closing Date. If any Underwriter or Underwriters so default and the
aggregate number of shares of Offered Securities with respect to which such
default or defaults occur exceeds 10% of the total number of shares of Offered
Securities that the Underwriters are obligated to purchase on such Closing Date
and arrangements satisfactory to CSFBC, the Company and the Selling Shareholder
for the purchase of such Offered Securities by other persons are not made within
36 hours after such default, this Agreement will terminate without liability on
the part of any non-defaulting Underwriter, the Company or the Selling
Shareholder, except as provided in Section 9 (provided that if such default
occurs with respect to Optional Securities after the First Closing Date, this
Agreement will not terminate as to the Firm Securities or any Optional
Securities purchased prior to such termination). In the event of any default by
one or more Underwriters as described in this Section 8, the Representatives
shall have the right to postpone the First Closing Date or the Optional Closing
Date, as the case may be, established as provided in Section 3 hereof for not
more than seven business days in order that any necessary changes may be made in
the arrangements or documents for the purchase and delivery of the Firm
Securities or Optional Securities, as the case may be. As used in this
Agreement, the term "UNDERWRITER" includes any person substituted for an
Underwriter under this Section. Nothing herein will relieve a defaulting
Underwriter from liability for its default.

     9. SURVIVAL OF CERTAIN REPRESENTATIONS AND OBLIGATIONS. The respective
indemnities, agreements, representations, warranties and other statements of the
Selling Shareholder, of the Company or its officers and of the several
Underwriters set forth in or made pursuant to this Agreement will remain in full
force and effect, regardless of any investigation, or statement as to the
results thereof, made by or on behalf of any Underwriter, the Selling
Shareholder, the Company or any of their respective representatives, officers or
directors or any controlling person, and will survive delivery of and payment
for the Offered Securities. If this Agreement is terminated pursuant to Section
8 or if for any reason the purchase of the Offered Securities by the
Underwriters is not consummated, the Company and the Selling Shareholder shall
remain responsible for the expenses to be paid or reimbursed by it pursuant to
Section 5 and the respective obligations of the Company, the Selling Shareholder
and the Underwriters pursuant to Section 7 shall remain in effect, and if any
Offered Securities have been purchased hereunder the representations and
warranties in Section 2 and all obligations under Section 5 shall also remain in
effect. If the purchase of the Offered Securities by the Underwriters is not
consummated for any reason other than solely because of the termination of this
Agreement pursuant to Section 8 or the occurrence of any event specified in
clause (iii), (iv) or (v) of Section 6(c), the Company will reimburse the
Underwriters for all out-of-pocket expenses (including fees and disbursements of
counsel) reasonably incurred by them in connection with the offering of the
Offered Securities.

     10. NOTICES. All communications hereunder will be in writing and, if sent
to the Underwriters, will be mailed, delivered or telegraphed and confirmed to
the Representatives, c/o Credit Suisse First Boston Corporation, Eleven Madison
Avenue, New York, NY 10010-3629, Attention: Transactions Advisory Group, with a
copy to Clifford Chance Rogers & Wells LLP, 200 Park Avenue, New York, NY
10166, Attention: Robert E. King, Jr., or, if sent to the Company, will be
mailed, delivered or telegraphed and confirmed to it at Corporate Office
Properties Trust, 401 City Avenue, Suite 615, Bala Cynwyd, PA 19004-1126,
Attention: Clay W. Hamlin, III, with a copy to Morgan, Lewis & Bockius, LLP,
1701 Market Street, Philadelphia, PA 19103-2921, Attention: Eric L. Stern; or,
if sent to the Selling Shareholder, will be mailed, delivered or telegraphed and
confirmed to Constellation Real Estate, Inc. at 39 West Lexington Street,
Baltimore, MD 21201; Attention: Steven D. Kesler; provided, however, that any
notice to an Underwriter pursuant to Section 7 will be mailed, delivered or
telegraphed and confirmed to such Underwriter.


                                       32


     11. SUCCESSORS. This Agreement will inure to the benefit of and be binding
upon the parties hereto and their respective successors and the officers and
directors and controlling persons referred to in Section 7, and no other person
will have any right or obligation hereunder.

     12. REPRESENTATION OF UNDERWRITERS. The Representatives will act for the
several Underwriters in connection with this financing, and any action under
this Agreement taken by the Representatives jointly or by CSFBC will be binding
upon all the Underwriters.

     13. COUNTERPARTS. This Agreement may be executed in any number of
counterparts, each of which shall be deemed to be an original, but all such
counterparts shall together constitute one and the same Agreement.

     14. APPLICABLE LAW. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO PRINCIPLES
OF CONFLICTS OF LAWS.

     The Company hereby submits to the non-exclusive jurisdiction of the Federal
and state courts in the Borough of Manhattan in The City of New York in any suit
or proceeding arising out of or relating to this Agreement or the transactions
contemplated hereby.



                                       33




         If the foregoing is in accordance with the Representatives'
understanding of our agreement, kindly sign and return to the Company one of the
counterparts hereof, whereupon it will become a binding agreement among the
Company, the Selling Shareholder and the several Underwriters in accordance with
its terms.

                            Very truly yours,

                                CORPORATE OFFICE PROPERTIES TRUST


                                         By:
                                            -----------------------------------
                                             Name:
                                             Title:


                                CORPORATE OFFICE PROPERTIES, L.P.

                                By: CORPORATE OFFICE PROPERTIES TRUST,
                                      its sole general partner


                                         By:
                                            -----------------------------------
                                             Name:
                                             Title:


                                CONSTELLATION REAL ESTATE, INC.


                                         By:
                                            -----------------------------------
                                             Name:
                                             Title:


The foregoing Underwriting Agreement is hereby
  confirmed and accepted as of the date first above
  written.

     CREDIT SUISSE FIRST BOSTON CORPORATION
     A.G. EDWARDS & SONS, INC.
     LEGG MASON WOOD WALKER INCORPORATED
     MCDONALD INVESTMENTS INC.

        Acting on behalf of themselves and as the
          Representatives of the several Underwriters

     By: CREDIT SUISSE FIRST BOSTON CORPORATION

      By:
          --------------------------------------------
          Name:
          Title:



                                   SCHEDULE I




                                                                      NUMBER OF FIRM SECURITIES            TOTAL
                                                                            TO BE SOLD BY                NUMBER OF
                                                                      ---------------------------     FIRM SECURITIES
                                                                                        SELLING            TO BE
                          UNDERWRITER                                 COMPANY         SHAREHOLDER        PURCHASED
                          -----------                                 --------        -----------     ---------------
                                                                                             
Credit Suisse First Boston Corporation.........................        270,216          2,911,384         3,181,600
A.G. Edwards & Sons, Inc........................................       159,822          1,721,978         1,881,800
Legg Mason Wood Walker, Incorporated............................       159,823          1,721,977         1,881,800
McDonald Investments Inc., a KeyCorp Company....................       159,823          1,721,977         1,881,800
BB&T Capital Markets, a division of
  Scott & Strongfellow, Inc.....................................        24,714            266,286           291,000
Ferris, Baker Watts, Incorporated...............................        24,715            266,285           291,000
Janney Montgomery Scott LLC.....................................        24,715            266,285           291,000
                                                                     ---------        -----------       -----------
         Total.................................................        823,828          8,876,172         9,700,000
                                                                     =========        ===========       ===========







                                   SCHEDULE II

                                  SUBSIDIARIES




                                                                JURISDICTION OF
                     NAME                                    INCORPORATION/FORMATION          FOREIGN QUALIFICATION
                     ----                                    -----------------------          ---------------------
                                                                                        
LIMITED & GENERAL PARTNERSHIPS
Blue Bell Investment Company, L.P.                                   Delaware                           PA
Corporate Office Properties, L.P.                                    Delaware                       MD, NJ, PA
Corporate Gateway General Partnership                                   PA
Comcourt Investors, L.P.                                             Delaware                           PA
COPT Gateway, L.P.                                                      PA
Gateway Central Limited Partnership                                     PA
South Brunswick Investors, L.P.                                      Delaware                           NJ
6385 Flank Drive, L.P.                                                  PA

CORPORATIONS
Corporate Office Management, Inc.                                    Maryland                     NJ, DE, VA, PA
Corporate Office Properties Holdings, Inc.                           Delaware                         PA, NJ
COPT Acquisitions, Inc.                                              Delaware                       PA, NJ, MD

LIMITED LIABILITY COMPANIES
Airport Square II, LLC                                               Maryland
Delaware Airport III, LLC                                            Delaware                           MD
Airport Square IV, LLC                                               Maryland
Airport Square V, LLC                                                Maryland
Airport Holdings Square VI and VII, LLC                              Delaware                           MD
Delaware Airport VIII, LLC                                           Delaware                           MD
Delaware Airport IX, LLC                                             Delaware                           MD
Airport Square X, LLC                                                Maryland
Airport Square XI, LLC                                               Maryland
Airport Square XIII, LLC                                             Maryland
Airport Square XIV, LLC                                              Maryland
Airport Square XV, LLC                                               Maryland
Airport Square XIX, LLC                                              Maryland
Airport Square XX, LLC                                               Maryland
Airport Square XXI, LLC                                              Maryland
Airport Square XXII, LLC                                             Maryland
Airport Square Partners, LLC                                         Maryland
Airport Square, LLC                                                  Maryland
Airport Square Holdings, I, LLC                                      Delaware                           MD
Atrium Building, LLC                                                 Maryland
Brown's Wharf, LLC                                                   Maryland
Commons Office Research, LLC                                         Maryland
Concourse 1304, LLC                                                  Maryland
COPT Columbia, LLC                                                   Maryland
COPT Concourse, LLC                                                  Delaware






                              SCHEDULE II (CONT'D.)
                                  SUBSIDIARIES



                                                                  JURISDICTION OF
                   NAME                                       INCORPORATION/FORMATION          FOREIGN QUALIFICATION
                   ----                                       -----------------------          ---------------------
                                                                                         
LIMITED LIABILITY COMPANIES (CONT.)
COPT Gate 6700-6708-6724, LLC                                         Maryland
COR, LLC                                                              Maryland
Corporate Development Services, LLC                                   Maryland
Corporate Gatespring, LLC                                             Maryland
Corporate Gatespring II, LLC                                          Maryland
Corporate Management Services, LLC                                    Maryland
Corporate Realty Management, LLC                                      Maryland                   DC, VA, DE, PA, NJ
Corporate Realty Advisors, LLC                                        Maryland
Cornucopia Holdings, LLC                                              Maryland
Cornucopia Holdings II, LLC                                           Maryland
CRM/Edgewood Property Services, LLC                                   Maryland
Cuaba Associates, LLC                                                New Jersey
Gateway 44, LLC                                                       Maryland
Gateway 70, LLC                                                       Maryland
Honeyland 108, LLC                                                    Maryland
Lakeview at the Greens, LLC                                           Maryland
Martin G. Knott & Associates, LLC                                     Maryland
NBP One, LLC                                                          Maryland
NBP 131-133-141, LLC                                                  Maryland
NBP 132, LLC                                                          Maryland
NBP 134, LLC                                                          Maryland
NBP 135, LLC                                                          Maryland
NBP 201, LLC                                                          Maryland
NBP 221, LLC                                                          Maryland
NBP Retail, LLC                                                       Maryland
9690 Deereco Road, LLC                                                Maryland
Princeton Executive, LLC                                             New Jersey
7200 Riverwood, LLC                                                   Maryland
7318 Parkway Drive Enterprises, LLC                                   Maryland
7321 Parkway Drive Enterprises, LLC                                   Maryland
7240 Parkway Drive Enterprises, LLC                                   Maryland
6711 Gateway, LLC                                                     Maryland
6731 Gateway, LLC                                                     Maryland
68 Culver, LLC                                                       New Jersey
St. Barnabas, LLC                                                     Maryland
Tech Park I, LLC                                                      Maryland
Tech Park II, LLC                                                     Maryland
Tech Park IV, LLC                                                     Maryland
Three Centre Park, LLC                                                Maryland
COPT Chantilly LLC                                                    Virginia
COPT Gate U3, LLC                                                     Maryland
NBP 140, LLC                                                          Maryland
NBP Huff & Puff, LLC                                                  Maryland






                                  SCHEDULE III

                               MATERIAL DOCUMENTS


     Amended and Restated Registration Rights Agreement, dated March 16, 1998,
for the benefit of certain shareholders of the Company (filed with the Company's
Quarterly Report on Form 10-Q on August 12, 1998 and incorporated herein by
reference).

     Second Amended and Restated Limited Partnership Agreement of the Operating
Partnership, dated December 7, 1999 (filed with the Company's Annual Report on
Form 10-K on March 16, 2000 and incorporated herein by reference).

     First Amendment to Second Amended and Restated Limited Partnership
Agreement of the Operating Partnership, dated December 21, 1999 (filed with the
Company's Annual Report on Form 10-K on March 16, 2000 and incorporated herein
by reference).

     Second Amendment to Second Amended and Restated Limited Partnership
Agreement of the Operating Partnership, dated December 21, 1999 (filed with the
Company's Post Effective Amendment No. 2 to Form S-3, dated November 1, 2000
(Registration Statement No. 333-71807), and incorporated herein by reference).

     Third Amendment to Second Amended and Restated Limited Partnership
Agreement of the Operating Partnership, dated September 29, 2000 (filed with the
Company's Post Effective Amendment No. 2 to Form S-3, dated November 1, 2000
(Registration Statement No. 333-71807), and incorporated herein by reference).

     Sixth Amendment to Second Amended and Restated Limited Partnership
Agreement of the Operating Partnership, dated April 3, 2001 (filed with the
Company's Current Report on Form 8-K, dated March 30, 2001, and incorporated
herein by reference).

     Registration Rights Agreement, dated September 28, 1998, for the benefit of
certain shareholders of the Company.

     Senior Secured Credit Agreement, dated October 13, 1997, (filed with the
Company's Current Report on Form 8-K on October 29, 1997, and incorporated
herein by reference).

     Amended and Restated Senior Secured Credit Agreement, dated August 31,
1998, between the Company, the Operating Partnership, Any Mortgaged Property
Subsidiary and Bankers Trust Company as Agent.

     Project Consulting and Management Agreement, dated September 28, 1998,
between Constellation Properties, Inc. and COMI (filed with the Company's
Current Report on Form 8-K on October 13, 1998 and incorporated herein by
reference).

     Agreement for Services, dated September 28, 1998, between the Company and
Corporate Office Management, Inc.

     Promissory Note dated October 22, 1998, in the amount of $ 85,000,000 made
by the Operating Partnership in favor of Teachers Insurance and Annuity
Association of America.





                                   SCHEDULE IV

                           SUBSIDIARIES - MLB OPINION


Corporate Office Properties, L.P.
Corporate Office Management, Inc.
Corporate Realty Management, LLC
Corporate Development Services, LLC
Blue Bell Investment Company, L.P.
South Brunswick Investors, L.P.







                                   SCHEDULE V

                          SUBSIDIARIES - GURLEY OPINION


NBP One, LLC
Airport Square II, LLC
Airport Square XX, LLC
NBP 131-133-141, LLC
NBP 135, LLC
7200 Riverwood, LLC
Corporate Gatespring, LLC
St. Barnabas, LLC