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Item 6. Exhibit (10)(k)


                     WASHINGTON REAL ESTATE INVESTMENT TRUST
                     SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN

                                 (July 1, 2002)

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                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                              Page
                                                                              ----
<S>                                                                           <C>
ARTICLE I.    PURPOSE .......................................................    2
     1.1    Establishment ...................................................    2
     1.2    Purpose .........................................................    2
     1.3    Compliance ......................................................    2

ARTICLE II.   DEFINITIONS ...................................................    2
     2.1    Accrued Benefit .................................................    2
     2.2    Administrator ...................................................    2
     2.3    Board ...........................................................    2
     2.4    Code ............................................................    2
     2.5    Committee .......................................................    3
     2.6    Company .........................................................    3
     2.7    ERISA ...........................................................    3
     2.8    Plan ............................................................    3
     2.9    Vested Interest .................................................    3

ARTICLE III.  ELIGIBILITY AND PARTICIPATION .................................    3
     3.1    Eligibility .....................................................    3
     3.2    Retirement Benefits .............................................    3
     3.3    Death Benefits ..................................................    3

ARTICLE IV.   ADMINISTRATION ................................................    4
     4.1    Administration ..................................................    4
     4.2    No Liability of Committee Members ...............................    4
     4.3    Claims Procedures ...............................................    4

ARTICLE V.    MISCELLANEOUS .................................................    6
     5.1    General Creditor Status .........................................    6
     5.2    Change in Control or other Discontinuance .......................    6
     5.3    Non-Alienation of Benefits ......................................    6
     5.4    Payments to Persons other than the CEO ..........................    6
     5.5    Amendment or Termination ........................................    6
     5.6    Effect of Trust Fund ............................................    7
     5.7    Unfunded Plan: Governing Law ....................................    7
     5.8    Taxes ...........................................................    7
     5.9    Other Plans .....................................................    7
     5.10   Not an Employment Contract ......................................    7
     5.11   Forfeiture ......................................................    7
     5.12   Captions ........................................................    7
     5.13   Severability ....................................................    7
     5.14   Effective Date ..................................................    8
</TABLE>

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                     SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN

                                   ARTICLE I.
                                     PURPOSE

     1.1 Establishment. Washington Real Estate Investment Trust (the "Company")
has established this Supplemental Executive Retirement Plan effective as of July
1, 2002 for the benefit of Edmund B. Cronin, Jr. Chairman of the Board,
President and Chief Executive Officer ("CEO").

     1.2 Purpose. The Company intends by the adoption of this Plan to recognize
the value to the Company of past and present services provided by the CEO and to
encourage his continued service with the Company by making more adequate
provision for his future retirement security.

     1.3 Compliance. This Plan is intended to be an unfunded plan for purposes
of the Code and Title I of ERISA. It is the Company's intent that this Plan be
exempt from ERISA's provisions to the maximum extent permitted by law. This Plan
is intended to be an unfunded "top-hat" plan maintained primarily for a select
group of management or highly-compensated employees under Sections 201(2),
301(a)(3), and 401(a)(1) of ERISA, and therefore is not subject to participation
and vesting, funding and fiduciary requirements under ERISA.

                                   ARTICLE II.
                                   DEFINITIONS

     When used herein, the following terms shall have the following meanings:

     2.1 "Accrued Benefit" means the annual amount of the retirement benefit
which the CEO has earned as of any particular time under the Plan. The Accrued
Benefit shall mean the product of (i) Two Hundred Thousand Dollars ($200,000)
multiplied by (ii) a fraction, the numerator of which is the number of whole
months which have elapsed from the date of the CEO's sixty fifth (65/th/)
birthday and the denominator of which is the number of whole months between the
CEO's sixty fifth (65/th/) birthday and the CEO's seventieth (70/th/) birthday.
For these purposes, the number of months to be included in the denominator shall
not include any months subsequent to the date of the CEO's termination of
employment with the Company for any reason.

     2.2 "Administrator" means the Senior Vice President of Administration of
Washington Real Estate Investment Trust.

     2.3 "Board" means the Board of Trustees of Washington Real Estate
Investment Trust.

     2.4 "Code" means the Internal Revenue Code of 1986, as now in effect or as
hereafter amended. All citations to sections of the Code are to such sections as
they may from time to time be amended or renumbered.

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     2.5 "Committee" means the Compensation Committee of the Board of Trustees
of Washington Real Estate Investment Trust.

     2.6 "Company" means Washington Real Estate Investment Trust.

     2.7 "ERISA" means the Employee Retirement Income Security Act of 1974, as
amended.

     2.8 "Plan" means this Supplemental Executive Retirement Plan of Washington
Real Estate Investment Trust.

     2.9 "Vested Interest" shall mean the CEO's right to receive a benefit from
the Plan. The CEO shall vest in accordance with the following schedule for each
year of continuous employment with the Company measured by reference to his
birthday and commencing with the CEO's sixty-fifth (65th) birthday:

              Years of Continuous Employment              Percentage Vested
              ------------------------------              -----------------

                            1                                     0%
                            2                                     0%
                            3                                    50%
                            4                                    75%
                            5                                   100%

The CEO shall be 100% vested upon his seventieth (70th) birthday, if having
remained employed through said date. In addition, the CEO shall become 100%
vested in the event of his termination of employment prior to his seventieth
(70th) birthday due to the incurrence of a total and permanent disability (as
defined in the Company's long-term disability plan). In addition, the Board of
Trustees may, in its sole and absolute discretion, elect to accelerate the rate
of vesting in whole or in part at any time.

                                  ARTICLE III.
                          ELIGIBILITY AND PARTICIPATION

     3.1 Eligibility. The CEO shall be the only employee of the Company eligible
to participate in this Plan.

     3.2 Retirement Benefits. Upon his termination of employment from the
Company for any reason other than death or a discharge due to gross negligence
or gross misconduct, the CEO will be entitled to receive an annual benefit,
payable in equal monthly amounts and commencing on the first day of the month
following the CEO's termination of employment, equal to his Accrued Benefit
times his Vested Interest. As such, in the event the CEO continues in the
employment of the Company until his seventieth (70th) birthday, the annual
benefit to be paid to the CEO shall be $200,000. Such benefit shall continue to
be paid to the CEO through the CEO's lifetime and shall terminate on the last
day of the month following the CEO's death.

     3.3 Death Benefits.

                                       -3-

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          (a)  In the event the CEO dies while employed by the Company, no death
               benefit will be paid under this Plan to the CEO's beneficiary.

          (b)  In the event the CEO dies subsequent to a termination of
               employment from the Company for any reason other than a discharge
               due to gross negligence or gross misconduct, and if the CEO had
               not previously received at least one hundred and eighty (180)
               monthly payments under the Plan, then the beneficiary of the CEO
               shall continue to receive from the Plan the same monthly payment
               as had been made to the CEO until the combination of the number
               of monthly payments made to the CEO prior to his death and the
               number of monthly payments made to the CEO's beneficiary equals
               one hundred and eighty (180).

                                  ARTICLE IV.
                                 ADMINISTRATION

     4.1 Administration. The Plan shall be administered by the Committee. The
Committee shall have all powers necessary to carry out the provisions of the
Plan, including, without reservation, discretionary authority to interpret the
provisions of the Plan, and the power to delegate to other persons the duty to
perform administrative matters and the discretionary authority to interpret the
provisions of the Plan.

     4.2 No Liability of Committee Members. No member of the Committee shall be
personally liable by reason of any contract or other instrument executed by such
member or on his or her behalf in his or her capacity as a member of the
Committee nor for any mistake of judgment made in good faith, and the Company
shall indemnify and hold harmless each employee, officer or director of the
Company to whom any duty or power relating to the administration or
interpretation of the Plan may be allocated or delegated, against any cost or
expense (including counsel fees) or liability (including any sum paid in
settlement of a claim) arising out of any act or omission to act in connection
with the Plan unless arising out of such person's own fraud or bad faith;
provided, however, that approval of the Board shall be required for the payment
of any amount in settlement of a claim against the Committee or any member of
the Committee.

     4.3 Claims Procedures. Claims for benefits under the Plan shall be
submitted in writing to and decided by the person designated by the Committee. A
claimant or his duly authorized representative may review pertinent documents
and may submit issues and comments in writing prior to the time when a decision
is rendered on the claim. Under normal circumstances a final decision on a
claimant's request for benefits shall be made within ninety (90) days after
receipt of the claim. However, if special circumstances require an extension of
time to process a claim, a final decision may be deferred up to one hundred
eighty (180) days after receipt of the claim if prior to the end of the initial
ninety (90) day period the claimant is furnished written notice of the special
circumstances requiring the extension and the anticipated date of a final
decision. If the claim is denied, within the applicable period of time set out
above, the claimant shall receive written notification of the denial, which
notice shall set forth in a manner reasonably calculated to be understood by
such claimant (i) the specific reason or reasons for the denial, (ii) specific
reference to the pertinent provision of the Plan on which the

                                      -4-

<PAGE>

denial is based, (iii) a description of any additional material or information
necessary for the claimant to perfect such claim and an explanation of why such
material or information is necessary, and (iv) an explanation of the Plan's
review procedure. If such a notice is not furnished and such claim has not been
allowed within the ninety (90) day period after receipt of the claim, such claim
shall be deemed to have been denied.

         In the event a claim is denied or in the event no action is taken on
the claim within the above-described period(s) of time, the following procedure
shall be used:

                (a) First, in the event that the claimant does not timely
                    receive the above-described written notification, the
                    claimant's request for benefits shall be deemed to be denied
                    as of the last day of the relevant period and the claimant
                    shall be entitled to a full review of his or her claim in
                    accordance with the following provisions of this Section.

                (b) Second, a claimant is entitled to a full review of his or
                    her claim after actual or constructive notification of a
                    denial. A claimant or the authorized representative of a
                    claimant desiring a claim review must make a written request
                    to the Committee requesting such a review, which request
                    shall contain all information which the claimant wishes the
                    Committee to consider. Incident to the review, the claimant
                    or the claimant' s authorized representative will have the
                    right to inspect all documents pertaining to the claim and
                    to submit issues and comments in writing. The Committee may
                    conduct any independent investigation which it deems
                    necessary to render its decision.

A request for a review must be filed with the Committee within sixty (60) days
after the denial of the claim for benefits was actually or constructively
received by the claimant. If no request is received within the sixty (60) day
time limit, the denial of benefits will be final. However, if a request for
review of a denied claim is timely filed, the Committee must render its decision
under normal circumstances within sixty (60) days of the receipt of the request
for review. However, if special circumstances require an extension of time, the
decision may be delayed if prior to expiration of the initial sixty (60) day
period the claimant is notified of the extension, but must in any event be
rendered no later than one hundred twenty (120) days after the receipt of the
request. If the decision on review is not furnished the claimant within the
applicable time period(s) set out above, the claim shall be deemed denied on the
last day of the relevant period. All decisions of the Committee shall be in
writing setting forth in a manner reasonably calculated to be understood by the
claimant the specific reasons for whatever action has been taken, and the
provisions of the Plan on which the decision is based. A claimant shall be
precluded from bringing suit for benefits unless a review of the claimant's
benefit claim has been properly requested and an adverse decision on review
received. For all purposes of the Plan, said decisions on claims (where no
review is requested) and decisions or review (where review is requested) shall
be final, binding and conclusive on all interested persons as to participation
and benefit eligibility, the computation of the employee's amount of benefit and
as to any other matter of fact or interpretation relating to the Plan.

                                      -5-

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                                   ARTICLE V.
                                  MISCELLANEOUS

     5.1 General Creditor Status. To the extent that the CEO acquires a right to
receive payments from the Company under the Plan, such right shall be no greater
than the right of an unsecured general creditor of the Company and the CEO shall
have only the unsecured promise of the Company that such payment shall be made.
All payments to be made hereunder shall be paid from the general funds of the
Company and no special or separate fund other than a trust designed to qualify
as a "Rabbi Trust" shall be established and no segregation of assets shall be
made to assure payment of such amounts. The CEO and his surviving spouse or
other beneficiary shall have no right, title or interest in or to any
investments which the Company may make to aid it in meeting its obligations
under the Plan. All such assets shall be the property solely of the Company and
shall be subject to the claims of the Company's unsecured general creditors.

     5.2 Change in Control or other Discontinuance. The CEO shall become fully
vested under the Plan upon a change in control of the Company resulting in the
termination of the CEO as CEO of the controlling parent company. The obligations
of the Company under the Plan shall be binding upon any successor corporation or
organization resulting from the merger, consolidation or other reorganization or
from any reincorporation or change of name of the company, or upon any successor
corporation or organization succeeding to substantially all of the assets and
business of the Company. The Company agrees that it will make appropriate
provision for the preservation of the CEO's rights under the Plan in any
agreement or plan which it may enter into or adopt to effect such merger,
consolidation, reorganization, reincorporation, change of name or transfer of
assets.

     5.3 Non-Alienation of Benefits. To the extent permitted by law, the CEO and
his surviving spouse or other beneficiary shall not have the right to alienate,
anticipate, commute, sell, assign, transfer, pledge, encumber or otherwise
convey the right to receive any payments under the Plan, and any payments under
the Plan or rights thereto shall not be subject to the debts, liabilities,
contracts, engagements or torts of the CEO or his surviving spouse or other
beneficiary nor to attachment, garnishment or execution, nor shall they be
transferable by operation of law in the event of bankruptcy or insolvency. Any
attempt, whether voluntary or involuntary, to effect any such action shall be
null, void and of no effect.

     5.4 Payments to Persons other than the CEO. If the Committee shall find
that the CEO or the death beneficiary of the CEO, if applicable, is unable to
care for such person's affairs because of illness or accident, or has died, then
any payment due to the CEO or to his estate or to such death beneficiary, if
applicable (unless a prior claim therefor has been made by a duly appointed
legal representative), may, if the Committee so directs the Company (or trustee
in the event a trust fund is established in connection with the Plan), be paid
to such person's spouse, child, a relative, an institution maintaining or having
custody of such person, or any other person deemed by the Committee to be a
proper recipient on behalf of such person otherwise entitled to payment. Any
such payment shall be a complete discharge of the liability of the Plan, any
trust fund established in accordance with Section 5.6 hereof and the Company
therefor.

     5.5 Amendment or Termination. The Board may, with prospective or
retroactive effect, amend, suspend, or terminate the Plan or any portion thereof
at any time, and delegates to

                                      -6-

<PAGE>

the Committee the authority to adopt amendments which may be necessary or
appropriate to facilitate the administration, management and interpretation of
the Plan or to conform the Plan thereto, provided any such amendment does not
significantly affect the cost to the Company of maintaining the Plan. However,
no amendment, suspension or termination of the Plan shall without the consent of
the CEO impair or adversely affect any benefits accrued and vested under the
Plan as of the date of such action (determined as if the CEO then employed had
terminated his employment as of the date of such amendment, suspension or
termination).

     5.6  Effect of Trust Fund. The Company shall be responsible for the payment
of all benefits to the CEO as provided under the Plan. The Company may, in its
discretion, establish a trust to be used for the purpose of providing for the
payment of such benefits. Although such a trust may be irrevocable, its assets
shall be held for payment of the Company's general creditors in the event of the
Company's bankruptcy or insolvency. To the extent any benefits provided under
the Plan are paid from a trust, the Company shall have no further obligation to
pay that portion of the benefit due. If not paid from the trust, the benefits
shall remain the obligation of the Company.

     5.7  Unfunded Plan: Governing Law. As provided in Section 1.3, the Plan is
intended to constitute an unfunded deferred compensation arrangement for the CEO
and all rights thereunder shall be governed by and be construed in accordance
with the laws of the State of Maryland.

     5.8  Taxes. The amount of any taxes required to be withheld from the CEO's
distribution by an federal, state, or local government shall be deducted from
the distribution. The CEO shall bear any and all federal, state, or local or
other taxes imposed on amounts accrued under or distributed from the Plan. The
Company does not represent or guarantee that any particular federal or state,
income, payroll, personal property or other tax consequences will result from
participation in the Plan.

     5.9  Other Plans. Benefits payable under the Plan shall not be deemed
salary or other compensation to the CEO for the purpose of computing benefits to
which he may be entitled under any other plan or arrangement of the Company.

     5.10 Not an Employment Contract. This Plan shall not be deemed to
constitute a contract of employment between the Company and the CEO, nor shall
any provision herein restrict the right of the Company to discharge the CEO, or
restrict the right of the CEO to terminate his employment.

     5.11 Forfeiture. In the event that the CEO shall be terminated for gross
negligence or gross misconduct, this Plan shall terminate immediately and no
benefits or payments of any kind will be made hereunder.

     5.12 Captions. The captions preceding the Sections of the Plan have been
inserted solely as a matter of convenience and in no way define or limit the
scope or intent of any provision of the Plan.

     5.13 Severability. If any section of this Plan is held to be unenforceable,
it shall be severed and shall not effect the validity and enforceability of the
remaining sections hereof.

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     5.14 Effective Date. The Plan shall be effective as of July 1, 2002.

IN WITNESS WHEREOF, the Company and the CEO have hereunder executed their
understanding and agreement to the terms and conditions of this Plan. .

                                     By  /s/ John P. McDaniel
                                         ---------------------------------------
                                         John P. McDaniel
                                         Chairman of the Compensation
                                         Committee of the Board of Trustees
                                         of Washington Real Estate Investment
                                         Trust


                                         /s/ Edmund B. Cronin
                                         ---------------------------------------
                                         Edmund B. Cronin, Jr.
                                         Chairman of the Board, President
                                         And Chief Executive Officer
                                         Washington Real Estate Investment Trust

ATTEST:                                  DATE:

____________________________
Secretary

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