CONTRIBUTION AGREEMENT (FUTURE MEMBERSHIP INTEREST)

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EXHIBIT 10.45

CONTRIBUTION AGREEMENT

(FUTURE MEMBERSHIP INTEREST)

BY AND BETWEEN

THE OLIVER CARR COMPANY

A DISTRICT OF COLUMBIA CORPORATION,

AS CONTRIBUTOR

AND

COLUMBIA EQUITY, LP,

A VIRGINIA LIMITED PARTNERSHIP,

AS ACQUIRER

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TABLE OF CONTENTS

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ARTICLE I THE CONTRIBUTION.......................................................................................1

1.1 Contribution of Interests.....................................................................1

1.2 Consideration.................................................................................1

1.3 Redemption Rights for Units...................................................................2

1.4 Tax Consequences to Contributor...............................................................2

ARTICLE II REPRESENTATIONS AND COVENANTS.........................................................................2

2.1 Representations by Acquirer...................................................................2

2.2 Representations by Contributor................................................................3

2.3 Covenants of Acquirer.........................................................................5

2.4 Covenants of Contributor......................................................................6

ARTICLE III Conditions Precedent to the Closing..................................................................7

3.1 Conditions to Acquirer's Obligations..........................................................7

3.2 Conditions to Contributor's Obligations.......................................................7

ARTICLE IV Closing and Closing Documents.........................................................................8

4.1 Closing.......................................................................................8

4.2 Contributor's Deliveries......................................................................8

4.3 Acquirer's Deliveries.........................................................................8

4.4 Fees and Expenses; Closing Costs..............................................................9

4.5 Adjustments...................................................................................9

ARTICLE V Miscellaneous..........................................................................................9

5.1 Notices.......................................................................................9

5.2 Entire Agreement; Modifications and Waivers; Cumulative Remedies.............................10

5.3 Exhibits.....................................................................................10

5.4 Successors and Assigns.......................................................................10

5.5 Article Headings.............................................................................10

5.6 Governing Law................................................................................10

5.7 Counterparts.................................................................................11

5.8 Survival.....................................................................................11

5.9 Severability.................................................................................11

5.10 Attorneys' Fees..............................................................................11

EXHIBITS

A Assignment and Assumption Agreement

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CONTRIBUTION AGREEMENT

THIS CONTRIBUTION AGREEMENT (this "Agreement") is made as of this 7th

day of January, 2005 by and between The Oliver Carr Company, a District of

Columbia corporation ("Contributor"); and Columbia Equity, LP, a Virginia

limited partnership ("Acquirer").

RECITALS

A. Carr Capital Corporation, a District of Columbia corporation

("CCC") intends to sponsor a publicly-owned real estate investment trust (the

"REIT"), which REIT will own property and membership interests in entities with

direct or indirect ownership over various real properties and improvements

located thereon, contributed by and purchased from Contributor and other

entities in exchange for partnership units (the "Units") in Acquirer.

B. Contributor desires to pledge and contribute 100% of any

ownership interests acquired by Contributor during the period between the date

first written above and the Closing Date (as defined below) in any entity with

direct or indirect ownership interests in any commercial office property

("Property") in the Greater Washington, DC market (the "Interests"), to

Acquirer, on the terms and conditions hereinafter set forth.

C. Acquirer desires to acquire the Interests from Contributor, on

the terms and conditions hereinafter set forth.

AGREEMENT

NOW, THEREFORE, for and in consideration of the mutual covenants herein

contained, the parties hereto agree as follows:

ARTICLE I

THE CONTRIBUTION

1.1 Contribution of Interests. Contributor agrees to contribute,

transfer, assign and convey the Interests to Acquirer, and Acquirer agrees to

acquire and accept transfer of the Interests pursuant to the terms and

conditions set forth in this Agreement. The Interests shall be transferred to

Acquirer free and clear of all liens, encumbrances, security interests, prior

assignments or conveyances, conditions, restrictions, voting agreements, claims,

and any other matters affecting title thereto.

1.2 Consideration. The total consideration (the "Consideration")

for which Contributor agrees to contribute and assign the Interests to Acquirer,

and which Acquirer agrees to pay or deliver to Contributor, subject to the terms

of this Agreement, shall be the issuance to Contributor of a number of Units

equal to (a) the Contributor's actual cash investment in the Interests, plus a

rate of return calculated on such investment from the date it is made until the

Closing Date at the Libor Rate (as defined below), (b) divided by the price per

share at which the common stock, $.001 par value per share, (the "Common Stock")

of the REIT, is offered to the public in the underwritten initial public

offering of the Common Stock (the "IPO"). The term Libor Rate shall mean (a) the

rate described as the "London Interbank Offered Rate" for one month in the Money

Rates Section of the Wall Street Journal, determined on the Closing Date, plus

(b) eight hundred (800) basis points. On the Closing Date, the Units shall be

issued to Contributor. Upon the request of Contributor, Acquirer shall issue

certificates reflecting Contributor's ownership of Units. The

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certificates evidencing the Units will bear appropriate legends indicating (i)

that the Units have not been registered under the Securities Act of 1933, as

amended ("Securities Act"), and (ii) that Acquirer's Amended and Restated

Agreement of Limited Partnership (the "Partnership Agreement") restricts the

transfer of the Units. Upon receipt of the Units and execution and delivery of

the Partnership Agreement, Contributor shall become a limited partner of

Acquirer.

1.3 Redemption Rights for Units. Each Unit shall be redeemable, at

the option of the holder, in accordance with, but subject to the restrictions

contained in, the Partnership Agreement; provided, however, that such redemption

option may not be exercised prior to the first anniversary of the Closing Date.

1.4 Tax Consequences to Contributor. Notwithstanding anything to

the contrary contained in this Agreement, including without limitation the use

of words and phrases such as "sell," "sale," purchase," and "pay," the parties

hereto acknowledge and agree that it is their intent that the transaction

contemplated hereby be treated for federal income tax purposes as the

contribution of the Interests by Contributor to Acquirer in exchange for Units

pursuant to Section 721 of the Internal Revenue Code of 1986, as amended (the

"Code"), and not as a transaction in which Contributor is acting other than in

its capacity as a prospective partner of Acquirer.

ARTICLE II

REPRESENTATIONS AND COVENANTS

2.1 Representations by Acquirer. Acquirer hereby represents and

warrants unto Contributor that the following statements are true, correct, and

complete in every material respect as of the date of this Agreement and will be

true, correct, and complete as of the Closing Date:

(a) Organization and Power. Acquirer is duly organized

and validly existing, under the laws of the Commonwealth of Virginia, and has

full right, power, and authority to enter into this Agreement and to perform all

of its obligations under this Agreement; and, the execution and delivery of this

Agreement and the performance by Acquirer of its obligations under this

Agreement have been duly authorized by all requisite action of Acquirer and

require no further action or approval of Acquirer's partners or of any other

individuals or entities in order to constitute this Agreement as a binding and

enforceable obligation of Acquirer.

(b) Noncontravention. Neither the entry into nor the

performance of, or compliance with, this Agreement by Acquirer has resulted, or

will result, in any violation of, or default under, or result in the

acceleration of, any obligation under the Partnership Agreement, or any

mortgage, indenture, lien agreement, note, contract, permit, judgment, decree,

order, restrictive covenant, statute, rule, or regulation applicable to

Acquirer.

(c) Litigation. There is no action, suit, or proceeding,

pending or known to be threatened, against or affecting Acquirer in any court or

before any arbitrator or before any federal, state, municipal, or other

governmental department, commission, board, bureau, agency or instrumentality

which (i) in any manner raises any question affecting the validity or

enforceability of this Agreement, (ii) would reasonably be expected to

materially and adversely affect the business, financial position, or results of

operations of Acquirer, or (iii) would

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reasonably be expected to materially and adversely affect the ability of

Acquirer to perform its obligations hereunder, or under any document to be

delivered pursuant hereto.

(d) Units Validly Issued. The Units, when issued, will

have been duly and validly authorized and issued, free of any preemptive or

similar rights, and will be fully paid and nonassessable, without any obligation

to restore capital except as required by the Virginia Revised Uniform Limited

Partnership Act (the "Limited Partnership Act"). Upon execution and delivery of

the Partnership Agreement by Contributor, Contributor shall be admitted as a

limited partner of Acquirer as of the Closing Date and shall be entitled to all

of the rights and protections of a limited partner under the Limited Partnership

Act and the provisions of the Partnership Agreement, with the same rights,

preferences, and privileges as all other limited partners on a pari passu basis.

(e) Consents. Each consent, approval, authorization,

order, license, certificate, permit, registration, designation, or filing by or

with any governmental agency or body necessary for the execution, delivery, and

performance of this Agreement or the transactions contemplated hereby by

Acquirer has been obtained.

(f) Bankruptcy with respect to Acquirer. No Act of

Bankruptcy has occurred with respect to Acquirer. As used herein, "Act of

Bankruptcy" shall mean if a party hereto shall (A) apply for or consent to the

appointment of, or the taking of possession by, a receiver, custodian, trustee

or liquidator of itself or of all or a substantial part of its property, (B)

admit in writing its inability to pay its debts as they become due, (C) make a

general assignment for the benefit of its creditors, (D) file a voluntary

petition or commence a voluntary case or proceeding under the Federal Bankruptcy

Code (as now or hereafter in effect), (E) be adjudicated bankrupt or insolvent,

(F) file a petition seeking to take advantage of any other law relating to

bankruptcy, insolvency, reorganization, winding-up or composition or adjustment

of debts, (G) fail to controvert in a timely and appropriate manner, or

acquiesce in writing to, any petition filed against it in an involuntary case or

proceeding under the Federal Bankruptcy Code (as now or hereafter in effect), or

(H) take any action for the purpose of effecting any of the foregoing.

(g) Brokerage Commission. Acquirer has not engaged the

services of, nor has it or will it or Contributor become liable to, any real

estate agent, broker, finder or any other person or entity for any brokerage or

finder's fee, commission or other amount with respect to the transactions

described herein on account of any action by Acquirer. Acquirer hereby agrees to

indemnify and hold Contributor and its employees, directors, members, partners,

affiliates and agents harmless against any claims, liabilities, damages or

expenses arising out of a breach of the foregoing. This indemnification shall

survive Closing or any termination of this Agreement.

2.2 Representations by Contributor. Contributor hereby represents

and warrants unto Acquirer that each and every one of the following statements

is true, correct, and complete in every material respect as of the date of this

Agreement and will be true, correct, and complete as of the Closing Date:

(a) Organization and Power. Contributor is duly

incorporated, validly existing, and in good standing as a corporation under the

laws of the District of Columbia. Contributor has full right, power, and

authority to enter into this Agreement and to assume and

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perform all of its obligations under this Agreement; and the execution and

delivery of this Agreement and the performance by Contributor of its obligations

hereunder have been duly authorized by all requisite action of Contributor and

require no further action or approval of Contributor's board of directors or

shareholders or of any other individuals or entities in order to constitute this

Agreement as a binding and enforceable obligation of Contributor.

(b) Noncontravention. Neither the entry into nor the

performance of, or compliance with, this Agreement by Contributor has resulted,

or will result, in any violation of, or default under, or result in the

acceleration of, any obligation under any bylaws, regulation, mortgage,

indenture, lien agreement, note, contract, permit, judgment, decree, order,

restrictive covenant, statute, rule, or regulation applicable to Contributor or

to the Interests.

(c) Litigation. There is no action, suit, claim, or

proceeding pending or threatened against or affecting Contributor or the

Interests in any court, or before any arbitrator, or before any federal, state,

municipal or other governmental department, commission, board, bureau, agency or

instrumentality which (A) in any manner raises any question affecting the

validity or enforceability of this Agreement, (B) would reasonably be expected

to materially and adversely affect the business, financial position or results

of operations of Contributor, (C) would reasonably be expected to materially and

adversely affect the ability of Contributor to perform its obligations

hereunder, or under any document to be delivered pursuant hereto, (D) would

reasonably be expected to create a lien on the Interests, any part thereof, or

any interest therein, or (E) would reasonably b