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                               SECURITY AGREEMENT

DATE:                             October 1, 2004

DEBTOR:                           Behringer Harvard REIT I, Inc.

DEBTOR'S MAILING ADDRESS:         Addison Circle One
                                  15601 Dallas Parkway, Suite 600
                                  Addison, Texas 75001

SECURED PARTY:                    First American Bank, SSB

SECURED PARTY'S MAILING ADDRESS:  One Lincoln Park
                                  8401 N. Central Expressway, Suite 500
                                  Dallas, Dallas County, Texas 75225

COLLATERAL (INCLUDING
 ALL ACCESSIONS):                 Money Market Account #0332594925 at First
                                  American Bank, in the name of Behringer
                                  Harvard REIT I, Inc. (the "MONEY MARKET
                                  Account")

OBLIGATIONS:                      That certain Promissory Note ("NOTE")
                                  executed by Behringer Harvard Holdings, LLC
                                  ("BORROWER"), in the maximum principal amount
                                  of $12,600,000.00, dated of even date
                                  herewith, payable to the order of Secured
                                  Party, and all amendments thereto or
                                  extensions thereof, and that certain Guaranty
                                  Agreement, executed by Debtor, covering the
                                  Note, dated of even date herewith, for the
                                  benefit of the Secured Party.

        Subject to the terms of this Security Agreement, Debtor grants to
Secured Party a security interest in the Collateral and all its proceeds to
secure payment and performance of Debtor's obligation in this Security Agreement
and all renewals and extensions of any of the Obligations.

DEBTOR'S WARRANTIES

        1.      FINANCING STATEMENT. Except for those in favor of Secured Party,
no financing statement covering the Collateral is filed in any public office.

        2.      OWNERSHIP. Debtor owns the Collateral and has the authority to
grant this security interest. Ownership is free from any setoff, claim,
restriction, lien, security interest, or encumbrance except this security
interest and liens for taxes not yet due.

        3.      FIXTURES AND ACCESSIONS. None of the Collateral is affixed to
real estate, is an

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accession to any goods, is commingled with other goods, or will become a
fixture, accession, or part of a product or mass with other goods except as
expressly provided in this Security Agreement.

        4.      FINANCIAL STATEMENTS. All information about Debtor's financial
condition provided to Secured Party was accurate when submitted, as will be any
information subsequently provided.

DEBTOR'S COVENANTS

        1.      PROTECTION OF COLLATERAL. Debtor will defend the Collateral
against all claims and demands adverse to Secured Party's interest in it and
will keep it free from all liens except those for taxes not yet due and from all
security interests except this one. The Collateral will remain in Debtor's
possession or control at all times, except as otherwise provided in this
Security Agreement. Debtor will maintain the Collateral in good condition and
protect it against misuse, abuse, waste, and deterioration except for ordinary
wear and tear resulting from its intended use.

        2.      SECURED PARTY'S COSTS. Debtor will pay all expenses incurred by
Secured Party in obtaining, preserving, perfecting, defending, and enforcing
this security interest or the Collateral and in collecting or enforcing the
Obligations. Expenses for which Debtor is liable include, but are not limited
to, taxes, assessments, reasonable attorney's fees, and other legal expenses.
These expenses will bear interest from the dates of payments at the highest rate
stated in notes that evidence the Obligations, and Debtor will pay Secured Party
this interest on demand at a time and place reasonably specified by Secured
Party. These expenses and interest will be part of the Obligations and will be
recoverable as such in all respects.

        3.      ADDITIONAL DOCUMENTS. Debtor will sign any agreements, financing
statements, or other documents or instruments that Secured Party considers
necessary to obtain, maintain, and perfect this security interest or to comply
with any relevant law.

        4.      NOTICE OF CHANGES. Debtor will immediately notify Secured Party
of any material change in the Collateral; change in Debtor's name, address, or
location; change in any matter warranted or represented in this agreement;
change that may affect this security interest; and any event of default.

        5.      SALE. Debtor will not sell, transfer, or encumber any of the
Collateral without the prior written consent of Secured Party.

        6.      RESERVE. Debtor covenants to preserve and maintain, at all
times, in the Money Market Account an amount of funds (the "RESERVE") equal to
or greater than the principal and interest outstanding under the Note, which
amount shall be over and above and in addition to any other reserve amounts that
the Debtor is required to maintain in the Money Market Account under any other
loans between the Borrower and the Secured Party.

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RIGHTS AND REMEDIES OF SECURED PARTY

        1.      GENERALLY. Secured Party may exercise any of the following
rights and remedies either before or after default:

                a.      take control of any proceeds of the Collateral;

                b.      release any Collateral in Secured Party's possession to
                        any debtor, temporarily or otherwise;

                c.      take control of any funds generated by the Collateral,
                        such as refunds from and proceeds of insurance, and
                        reduce any part of the Obligations accordingly or permit
                        Debtor to use such funds to repair or replace damaged or
                        destroyed Collateral covered by insurance; or

                d.      demand, collect, convert, redeem, settle, compromise,
                        receipt for, realize on, sue for, and adjust the
                        Collateral either in Secured Party's or Debtor's name,
                        as Secured Party desires.

        2.      INSURANCE. If Debtor fails to maintain insurance as required by
this Security Agreement or otherwise by Secured Party, then Secured Party may
purchase single-interest insurance coverage that will protect only Secured
Party. If Secured Party purchases this insurance, its premiums will become part
of the Obligations.

EVENTS OF DEFAULT

        Each of the following conditions is an event of default:

        1.      If the Borrower defaults in timely payment or performance of any
Obligations, covenant, or liability in any written agreement between Borrower
and Secured Party, or if the Debtor defaults in the performance of any term or
condition of this Security Agreement;

        2.      If any warranty, covenant, or representation made to Secured
Party by or on behalf of Debtor or Borrower proves to have been false in any
material respect when made;

        3.      If a receiver is appointed for Borrower, Debtor or any of the
Collateral;

        4.      If the Collateral is assigned for the benefit of creditors or,
to the extent permitted by law if bankruptcy or, insolvency proceedings commence
against or by any of these parties: Borrower (or either of the entities
comprising the borrower), Debtor; any partnership of which

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Debtor is a general partner; and any maker, drawer, acceptor, endorser,
guarantor, surety, accommodation party, or other person liable on or for any
part of the Obligations;

        5.      If any financing statement regarding the Collateral but not
related to this security interest and not favoring Secured Party is filed;

        6.      If any lien attaches to any of the Collateral; or

        7.      If any of the Collateral is lost, stolen, damaged, or destroyed,
unless it is promptly replaced with collateral of like quality or restored to
its former condition.

REMEDIES OF SECURED PARTY ON DEFAULT

        During the existence of any event of default, Secured Party may declare
the unpaid principal and earned interest of any of the Obligations immediately
due in whole or part, enforce the Obligations, and exercise any rights and
remedies granted by Chapter 9 of the Texas Uniform Commercial Code or by this
Security Agreement, including the following:

        1.      Require Debtor to deliver to Secured Party all books and records
relating to the Collateral;

        2.      Require Debtor to assemble the Collateral and make it available
to Secured Party at a place reasonably convenient to both parties;

        3.      Take possession of any of the Collateral and for this purpose
enter any premises where it is located if this can be done without breach of the
peace;

        4.      Sell, lease, or otherwise dispose of any of the Collateral in
accord with the rights, remedies, and duties of a secured party under Chapter 9
of the Texas Uniform Commercial Code after giving notice as required by such
chapter; unless the Collateral threatens to decline speedily in value, is
perishable, or would typically be sold on a recognized market. Secured Party
will give Debtor reasonable notice of any public sale of the Collateral or of a
time after which it may be otherwise disposed of without further notice to
Debtor; in this event, notice will be deemed reasonable if it is mailed, postage
prepaid, to Debtor at the address specified in this agreement at least ten days
before any public sale or ten days before the time when the Collateral may be
otherwise disposed of without further notice to Debtor;

        5.      Surrender any insurance policies covering the Collateral and
receive the unearned premium;

        6.      Apply any proceeds from disposition of the Collateral after
default in the manner specified in Chapter 9 of the Texas Uniform Commercial
Code, including payment of Secured Party's reasonable attorney's fees and court
expenses; and

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        7.      If disposition of the Collateral leaves the Obligations
unsatisfied, collect the deficiency from Borrower, Debtor or any guarantor of
the Obligations.

GENERAL PROVISIONS

        1.      PARTIES BOUND. Secured Party's rights under this Security
Agreement shall inure to the benefit of its successors and assigns. Assignment
of any part of the Obligations and delivery by Secured Party of any part of the
Collateral will fully discharge Secured Party from responsibility for that part
of the Collateral. If Debtor is more than one, all their representations,
warranties, and agreements are joint and several. Debtor's obligations under
this Security Agreement shall bind Debtor's personal representatives,
successors, and assigns.

        2.      WAIVER. Neither delay in exercise nor partial exercise of any of
Secured Party's remedies or rights shall waive further exercise of those
remedies or rights. Secured Party's failure to exercise remedies or rights does
not waive subsequent exercise of those remedies or rights. Secured Party's
waiver of any default does not waive further default. Secured Party's waiver of
any right in this Security Agreement or of any default is binding only if it is
in writing. Secured Party may remedy any default without waiving it.

        3.      REIMBURSEMENT. If Debtor fails to perform any of Debtor's
obligations, Secured Party may perform those obligations and be reimbursed by
Debtor on demand at the place where any note evidencing the Obligations is
payable for any sums so paid, including attorney's fees and other legal
expenses, plus interest on those sums from the dates of payment at the rate
stated in any such note for matured, unpaid amounts. The sum to be reimbursed
shall be secured by this Security Agreement.

        4.      INTEREST RATE. Interest included in the Obligations shall not
exceed the maximum amount of nonusurious interest that may be contracted for,
taken, reserved, charged, or received under law; any interest in excess of that
maximum amount shall be credited to the principal of the Obligations or, if that
has been paid, refunded. On any acceleration or required or permitted prepayment
of the Obligations, any such excess shall be canceled automatically as of the
acceleration or prepayment or, if already paid, credited on the principal amount
of the Obligations or, if the principal amount has been paid, refunded. This
provision overrides other provisions in this and all other instruments
concerning the Obligations.

        5.      MODIFICATIONS. No provisions of this Security Agreement shall be
modified or limited except by written agreement.

        6.      SEVERABILITY. The unenforceability of any provision of this
Security Agreement will not affect the enforceability or validity of any other
provision.

        7.      AFTER-ACQUIRED CONSUMER GOODS. This security interest shall
attach to after-acquired consumer goods only to the extent permitted by law.

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        8.      APPLICABLE LAW. This Security Agreement will be construed
according to Texas laws.

        9.      PLACE OF PERFORMANCE. This Security Agreement is to be performed
in the county of Secured Party's mailing address.

        10.     FINANCING STATEMENT. A carbon, photographic, or other
reproduction of this Security Agreement or any financing statement covering the
Collateral is sufficient as a financing statement.

        11.     PRESUMPTION OF TRUTH AND VALIDITY. If the Collateral is sold
after default, recitals in the bill of sale or transfer will be prima facie
evidence of their truth, and all prerequisites to the sale specified by this
agreement and by Chapter 9 of the Texas Uniform Commercial Code will be presumed
satisfied.

        12.     SINGULAR AND PLURAL. When the context requires, singular nouns
and pronouns include the plural.

        13.     PRIORITY OF SECURITY INTEREST. This security interest shall
neither affect nor be affected by any other security for any of the obligation.
Neither extensions of any of the obligation nor releases of any of the
Collateral will affect the priority or validity of this security interest with
reference to any third person.

        14.     CUMULATIVE REMEDIES. Foreclosure of this security interest by
suit does not limit Secured Party's remedies, including the right to sell the
Collateral under the terms of this Security Agreement. All remedies of Secured
Party may be exercised at the same or different times, and no remedy shall be a
defense to any other. Secured Party's rights and remedies include all those
granted by law or otherwise, in addition to those specified in this Security
Agreement.

        15.     AGENCY. Debtor's appointment of Secured Party as Debtor's agent
is coupled with an interest and will survive any disability of Debtor.

        16.     ATTACHMENTS INCORPORATED. The addendum indicated below is
attached to this Security Agreement and incorporated into it for all purposes:

        (_X_)   Addendum relating to accounts, inventory, documents, chattel
        paper, and general intangibles.

        (___)   Addendum relating to instruments.

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        17.     LOAN AGREEMENT. THIS WRITTEN LOAN AGREEMENT (AS DEFINED BY
SECTION 26.02 OF THE TEXAS UNIFORM COMMERCIAL CODE) REPRESENTS THE FINAL
AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR,
CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO
UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.

                                        DEBTOR:

                                        BEHRINGER HARVARD REIT I, INC.


                                        By:_________________________________
                                        Name:_______________________________
                                        Title:______________________________


                                        SECURED PARTY:

                                        FIRST AMERICAN BANK, SSB


                                        By:_________________________________
                                        Name:_______________________________
                                        Title:______________________________


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                         ADDENDUM TO SECURITY AGREEMENT
                 (ACCOUNTS, INVENTORY, DOCUMENTS, CHATTEL PAPER,
                              GENERAL INTANGIBLES)

Date:                October ___, 2004

Debtor:              Behringer Harvard REIT I, Inc.

Secured Party:       First American Bank, SSB

        The Collateral includes one or more of these classifications: accounts,
inventory, documents, chattel paper, and general intangibles; this Addendum
covering that Collateral applies to and is incorporated into the Security
Agreement to which it is attached.

DEBTOR'S WARRANTY

        No account debtors or other obligor whose debts or obligations are part
of the Collateral have any right to setoffs, counterclaims, or adjustments or
any defenses in connection with their debts or obligations.

DEBTOR'S COVENANTS

        1.      INFORMATION AND INSPECTION. At the time and in the form
specified by Secured Party, Debtor will furnish Secured Party any requested
information related to the Collateral, which may include:

                a.      all information necessary to identify any of the
                Collateral; and

                b.      shipping and delivery receipts evidencing the shipment
                of goods, and invoices evidencing receipt of and payment for
                inventory in the Collateral.

Debtor will also allow Secured Party to inspect the Collateral at any time and
place and to inspect and copy all records relating to the Collateral, as long as
these are accomplished without breach of the peace.

        2.      PARTIES LIABLE ON THE COLLATERAL. Debtor will preserve the
liability of all obligors on the Collateral, preserve the priority of all
security for the Collateral, and deliver to Secured Party the original
certificates of title on all motor vehicles included in the Collateral.

        3.      MODIFICATION OF COLLATERAL. Without the written consent of
Secured Party, Debtor will not agree to any modification of terms in any writing
related to the Collateral.

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        4.      DELIVERY OF RECEIPTS TO SECURED PARTY. On Secured Party's demand
Debtor will deposit all payments received as proceeds of Collateral in a special
bank account designated by Secured Party, who alone will have power of
withdrawal. Debtor will deposit the payments on receipt, in the form received,
and with any necessary endorsements as security for the Obligations described in
the Security Agreement. Secured Party may make any endorsements in Debtor's name
and behalf. Between receiving and depositing these payments, Debtor will not
mingle them with any of Debtor's other funds or property but will hold them
separate and in an express trust for Secured Party. Secured Party shall apply
all or part of these funds against the Obligations.

        5.      RECORDS OF COLLATERAL. Debtor will maintain accurate books and
records covering the collateral and showing the assignment of accounts in
Collateral to Secured Party. Only undisputed and unpaid amounts will be shown as
owed to Debtor on the books and any assignment schedule.

        6.      ACCOUNTS. Each account in the Collateral will represent the
valid, legally enforceable obligation of third parties and will not be evidenced
by any instrument or chattel paper.

        7.      CONSUMER CREDIT. If any Collateral or proceeds include
obligations of third parties to Debtor, the transactions creating those
obligations will conform in all respects to applicable state and federal
consumer credit law.

        8.      CHATTEL PAPER. By means satisfactory to Secured Party, Debtor
has perfected or will perfect a security interest in goods covered by chattel
paper in Collateral.

        9.      POSSESSION OF COLLATERAL. By delivering a copy of this Security
Agreement to the broker, seller, or other person in possession of Collateral
that is chattel paper or documents, Secured Party will effectively notify that
person of Secured Party's interest in the Collateral. Delivery of the copy of
the Security Agreement will also constitute Debtor's instruction to deliver to
Secured Party certificates or other evidence of the Collateral as soon as it is
available. Debtor will immediately deliver to Secured Party all chattel paper
and documents that are collateral in Debtor's possession. If that Collateral is
hereafter acquired, Debtor will deliver it to Secured Party immediately
following acquisition and either endorse it to Secured Party's order or give
Secured Party appropriate executed powers.

        10.     UNCERTIFICATED SECURITIES. If the collateral is uncertificated
securities, Secured Party's delivery of a copy of this Security Agreement to the
financial intermediary on whose books the Debtor's interest in the Collateral
appears will effectively notify the financial intermediary of Secured Party's
interest in the Collateral and will constitute Debtor's instruction that the
issuer of the securities register their pledge to Secured Party. Debtor agrees
to do everything required by Secured Party to complete the transfer and
perfection of this security interest.

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RIGHTS AND REMEDIES OF SECURED PARTY

        1.      GENERAL. Before or after default Secured Party may exercise any
or all of these rights and remedies:

                a.      contact account debtors directly to verify information
                        furnished by Debtor;

                b.      notify obligors on the Collateral to pay Secured Party
                        directly;

                c.      take control of all proceeds of and payments on any
                        Collateral and apply them against the Obligations; and

                d.      as Debtor's agent endorse any documents or chattel paper
                        that is Collateral or that represents proceeds of
                        Collateral.

        2.      LIABILITY. Secured Party has no obligation to collect any
account and will not be liable for failure to collect any account or for any act
or omission on the part of Secured Party or Secured Party's officers, agents, or
employees, except willful misconduct.

                                          DEBTOR:

                                          BEHRINGER HARVARD REIT I, INC.


                                          By:__________________________________
                                          Name:________________________________
                                          Title:_______________________________


                                          SECURED PARTY:

                                          FIRST AMERICAN BANK, SSB


                                          By:__________________________________
                                          Name:________________________________
                                          Title:_______________________________