EXHIBIT 10.1 MEMBERSHIP INTEREST SALE AGREEMENT BY AND BETWEEN KULEA, LLC, A VIRGINIA LIMITED LIABILITY COMPANY, AS SELLER AND COLUMBIA EQUITY LP, A VIRGINIA LIMITED PARTNERSHIP, AS PURCHASER TABLE OF CONTENTS

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EXHIBIT 10.1

MEMBERSHIP INTEREST SALE AGREEMENT

BY AND BETWEEN

KULEA, LLC,

A VIRGINIA LIMITED LIABILITY COMPANY,

AS SELLER

AND

COLUMBIA EQUITY LP,

A VIRGINIA LIMITED PARTNERSHIP,

AS PURCHASER

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TABLE OF CONTENTS

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ARTICLE I THE SALE............................................................. 1

1.1 Sale of Membership Interest...................................... 1

1.2 Purchase Price................................................... 1

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

2.1 Representations by Purchaser..................................... 2

2.2 Representations by Seller........................................ 3

2.3 Seller's Indemnity............................................... 5

2.4 Purchaser's Indemnity............................................ 5

2.5 Covenants of Purchaser........................................... 5

2.6 Covenants of Seller.............................................. 5

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

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

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

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

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

4.2 Seller's Deliveries.............................................. 8

4.3 Purchaser's Deliveries........................................... 9

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

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

ARTICLE V Miscellaneous........................................................ 11

5.1 Notices.......................................................... 11

5.2 Entire Agreement; Modifications and Waivers; Cumulative Remedies. 11

5.3 Exhibits......................................................... 12

5.4 Successors and Assigns........................................... 12

5.5 Article Headings................................................. 12

5.6 Governing Law.................................................... 12

5.7 Counterparts..................................................... 12

5.8 Survival......................................................... 12

5.9 Severability..................................................... 12

5.10 Attorneys' Fees.................................................. 12

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EXHIBITS

A Assignment

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MEMBERSHIP INTEREST SALE AGREEMENT

THIS MEMBERSHIP INTEREST SALE AGREEMENT (this "Agreement") is made as of

this 12th day of October, 2004 by and between Kulea, LLC, a Virginia limited

liability company ("Seller"); and Columbia Equity, LP, a Virginia limited

partnership ("Purchaser").

RECITALS

A. Carr Capital Greenbriar, LLC, a Virginia limited liability company (the

"LLC") is the owner of certain land located in Fairfax County, Virginia (the

"Land") and the office building and related improvements located thereon (the

"Improvements"), which Land and Improvements (collectively, the "Property") are

more commonly known as the Greenbriar office building.

B. Seller is the record and beneficial owner of seventy-five percent (75%)

("Seller's Share") of the membership interests in the LLC (the "Membership

Interest"). Seller desires to sell the Membership Interest to Purchaser, on the

terms and conditions hereinafter set forth.

C. Purchaser desires to purchase the Membership Interest from Seller, on

the terms and conditions hereinafter set forth.

D. Immediately prior to such purchase and sale of the Membership Interest,

Carr Capital/Holualoa Greenbriar, LLC, a Virginia limited liability company,

shall liquidate and each of its members, Holualoa Greenbriar, LLC, an Arizona

limited liability company and Carr Capital Real Estate Investments, LLC, a

Virginia limited liability company, (collectively, the "Liquidating LLC

Members") shall be admitted as members of the LLC, with a Fifteen and 79/100

percent (15.79%) membership interest in the LLC and a 53/100 percent (.53%)

membership interest in the LLC, respectively (the "Liquidation Transaction").

AGREEMENT

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

contained, the parties hereto agree as follows:

ARTICLE I

THE SALE

1.1 Sale of Membership Interest. Seller agrees to sell, transfer, assign

and convey the Membership Interest to Purchaser, and Purchaser agrees to accept

transfer of the Membership Interest pursuant to the terms and conditions set

forth in this Agreement. The Membership Interest shall be transferred to

Purchaser 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 Purchase Price. The purchase price (the "Purchase Price") for which

Seller agrees to sell and assign the Membership Interest to Purchaser, and which

Purchaser agrees to pay to

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Seller, subject to the terms of this Agreement, shall be equal to the amount of

Net Cash Flow (as such term is defined in the LLC's operating agreement (the

"LLC Operating Agreement")) that Seller would be entitled to receive pursuant to

Section 3.1 of the LLC Operating Agreement upon a hypothetical sale of the

Property for a sale price of Fifteen Million Three Hundred Thousand Dollars

($15,300,000) less the principal of an accrued interest on the mortgage loan

secured by the Property (the "Mortgage Loan"). The hypothetical sale shall be

based upon the assumption that the transfer taxes and recording taxes shall not

be payable, that there is no brokerage fee and that other fees and expenses

(subject to adjustment as set forth in Section 4.5) are as set forth in Exhibit

A attached hereto.

ARTICLE II

REPRESENTATIONS AND COVENANTS

2.1 Representations by Purchaser. Purchaser hereby represents and warrants

to Seller 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. Purchaser is duly organized and validly

existing as a limited partnership under the laws of the Commonwealth of

Virginia, and has full right, power, and authority to enter into this Agreement

and to assume and perform all of its obligations under this Agreement; and, the

execution and delivery of this Agreement and the performance by Purchaser of its

obligations under this Agreement have been duly authorized by all requisite

action of Purchaser and require no further action or approval of Purchaser's

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

Agreement as a binding and enforceable obligation of Purchaser.

(b) Noncontravention. Neither the entry into nor the performance of,

or compliance with, this Agreement by Purchaser has resulted, or will result, in

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

obligation under the partnership agreement of Purchaser, or any mortgage,

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

restrictive covenant, statute, rule, or regulation applicable to Purchaser.

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

known to be threatened, against or affecting Purchaser 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) could materially and adversely affect the business, financial

position, or results of operations of Purchaser, (iii) could materially and

adversely affect the ability of Purchaser to perform its obligations hereunder,

or under any document to be delivered pursuant hereto.

(d) 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

Purchaser has been obtained.

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(e) Brokerage Commission. Purchaser has not engaged the services of,

nor has it or will it or Seller 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 Purchaser. Purchaser hereby agrees to indemnify and

hold Seller 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 Seller. Seller hereby represents and warrants unto

Purchaser 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. Seller is duly organized, validly

existing, and in good standing as a limited liability company under the laws of

the Commonwealth of Virginia. Seller has full right, power, and authority to

enter into this Agreement and to assume and perform all of its obligations under

this Agreement; and the execution and delivery of this Agreement and the

performance by Seller of its obligations hereunder have been duly authorized by

all requisite action of Seller and require no further action or approval of

Seller's members or managers or of any other individuals or entities in order to

constitute this Agreement as a binding and enforceable obligation of Seller.

(b) Noncontravention. Neither the entry into nor the performance of,

or compliance with, this Agreement by Seller has resulted, or will result, in

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

obligation under any limited liability company agreement, operating agreement,

regulation, mortgage, indenture, lien agreement, note, contract, permit,

judgment, decree, order, restrictive covenant, statute, rule, or regulation

applicable to Seller or to the Membership Interest.

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

pending or threatened against or affecting Seller or the Membership Interest 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) could materially and adversely

affect the business, financial position or results of operations of Seller, (C)

could materially and adversely affect the ability of Seller to perform its

obligations hereunder, or under any document to be delivered pursuant hereto,

(D) could create a lien on the Membership Interest, any part thereof, or any

interest therein, or (E) could adversely affect the Membership Interest, any

part thereof, or any interest therein.

(d) Good Title. (A) Seller is the sole owner of the Membership

Interest, (B) Seller has good title to the Membership Interest, (C) the

Membership Interests are free and clear of all liens, encumbrances, pledges,

voting agreements and security interests whatsoever, and (D) Seller has not

granted any other person or entity an option to purchase or a right of first

refusal

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upon the Membership Interest nor are there any agreements or understandings

between Seller and any other person or entity with respect to the disposition of

the Membership Interest.

(e) No Consents. Each consent, approval, authorization, order,

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

any governmental agency or body necessary of the execution, delivery, and

performance of this Agreement or the transactions contemplated hereby by Seller

has been obtained or will be obtained on or before the Closing Date.

(f) Tax Matters. Seller has filed within the time and in the manner

prescribed by law all federal, state, and local tax returns and reports,

including but not limited to income, gross receipts, intangible, real property,

excise, withholding, franchise, sales, use, employment, personal property, and

other tax returns and reports, required to be filed by Seller under the laws of

the United States and of each state or other jurisdiction in which Seller

conducts business activities requiring the filing of tax returns or reports. All

tax returns and reports filed by Seller are true and correct in all material

respects. Seller has paid in full all taxes of whatever kind or nature for the

periods covered by such returns. Seller has not been delinquent in the payment

of any tax, assessment, or governmental charge or deposit and has no tax

deficiency or claim outstanding, assessed, threatened, or proposed against it.

The charges, accruals, and reserves for unpaid taxes on the books and records of

Seller as of the Closing Date are sufficient in all respects for the payment of

all unpaid federal, state, and local taxes of Seller accrued for or applicable

to all periods ended on or before the Closing Date. There are no tax liens,

whether imposed by the United States, any state, local, or other taxing

authority, outstanding against Seller or any of its assets. The federal, state,

and local tax returns of Seller have not been audited, nor has Seller received

any notice of any federal, state, or local audit.

(g) Bankruptcy with respect to Seller. No Act of Bankruptcy has

occurred with respect to Seller. As used herein, "Act of Bankruptcy" shall mean

if a party hereto or any member or manager thereof 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.

(h) Brokerage Commission. Seller has not engaged the services of,

nor has it or will it or Purchaser 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 Seller. Seller hereby agrees to indemnify and hold

Purchaser and its employees, directors, members, partners, affiliates and

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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.

2.3 Seller's Indemnity. Seller agrees to indemnify and hold Purchaser,

Columbia Equity Trust, Inc., a Maryland corporation (the "REIT"), and their

respective employees, directors, members, partners, affiliates and agents

harmless of and from all liabilities, losses, damages, costs, and expenses

(including reasonable attorneys' fees) which Purchaser or the REIT may suffer or

incur by reason of any breach of Seller's representations or warranties

contained in this Agreement, and by reason of any act or cause of action

occurring or accruing prior to the Closing Date and arising from the ownership

of the Membership Interest prior to the Closing Date.

2.4 Purchaser's Indemnity. Purchaser agrees to indemnify and hold Seller

and its employees, directors, members, partners, affiliates and agents harmless

of and from all liabilities, losses, damages, costs, and expenses (including

reasonable attorneys' fees) which Seller may suffer or incur by reason of any

breach of Purchaser's representations or warranties contained in this Agreement,

and by reason of any act or cause of action occurring or accruing subsequent to

the Closing Date and arising from the ownership of the Membership Interests or

the operation of the Property subsequen