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                                 PROMISSORY NOTE

$12,600,000.00                     Dallas, Texas           As of October 1, 2004

        FOR VALUE RECEIVED, the undersigned, BEHRINGER HARVARD HOLDINGS, LLC, a
Delaware limited liability company (hereinafter referred to as "BORROWER"),
promises to pay to the order of FIRST AMERICAN BANK, SSB, a Texas state savings
bank (hereinafter referred to as "LENDER"), the sum of Twelve Million Six
Hundred Thousand and No/100 Dollars ($12,600,000.00), or so much thereof as may
be advanced and outstanding, with interest thereon at the rate provided below.

        INTEREST RATE. This Promissory Note (the "NOTE") shall bear interest on
the unpaid principal balance hereof from day to day remaining from the date
hereof until maturity at the rate per annum, which interest rate (the "INTEREST
RATE") shall from day to day be equal to the LESSER of (a) the Maximum Legal
Rate (hereinafter defined) or (b) the rate which is the GREATER of (i) six
percent (6%) per annum, or (ii) one percent (1%) in excess of the Prime Rate
(hereinafter defined) in effect from day to day; provided, however, if at any
time the rate of interest specified in clause (b) preceding would exceed the
Maximum Legal Rate, thereby causing the interest on the indebtedness evidenced
by this Note to be limited to the Maximum Legal Rate, then any subsequent
reduction in the Prime Rate shall not reduce the rate of interest on the
indebtedness evidenced by this Note below the Maximum Legal Rate until the total
amount of interest accrued on the indebtedness evidenced by this Note equals the
amount of interest which would have accrued on the indebtedness evidenced by
this Note if the rate specified in clause (b) preceding had at all times been in
effect. As used herein, the term "PRIME RATE" means the variable rate of
interest per annum established from time to time in the Money Rates column of
THE WALL STREET JOURNAL (Central Edition) or, if such publication shall
designate two or more published rates as the "prime rate" as of any Business
Day, "Prime Rate" shall mean the rate of interest per annum publicly announced
by Lender as its prime rate in effect at its principal office in Dallas, Texas.
For each day that is not a Business Day, the "Prime Rate" shall be the "Prime
Rate" in effect on the immediately preceding Business Day. Changes in the Prime
Rate, as defined above, shall be effective from and including the Business Day
such change is published or announced, as the case may be. Each change in the
Interest Rate shall become effective, without notice to Borrower, on the
effective date of each change in the Prime Rate.

        MAXIMUM LEGAL RATE. As used herein, the term "MAXIMUM LEGAL RATE," shall
mean the maximum nonusurious interest rate, if any, that at any time or from
time to time may be contracted for, taken, reserved, charged, or received on the
indebtedness evidenced by this Note under the laws, which are presently in
effect, of the United States of America and the State of Texas applicable to the
Borrower and such indebtedness or, to the extent allowed by law, under such
applicable laws of the United States of America and the State of Texas which may
hereafter be in effect and which allow a higher maximum nonusurious interest
rate than applicable laws now allow. For purposes of determining the Maximum
Legal Rate under the laws of the State of Texas, the applicable rate ceiling
shall be (a) the "weekly ceiling" described in and computed in accordance with
the provisions of Section 303.303 of the Texas Finance Code, as amended, or

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(b) if the parties subsequently contract as allowed by Texas law, the quarterly
ceiling or annualized ceiling computed pursuant to Section 303.008 of the Texas
Finance Code, as amended; provided, however, if at any time the "weekly
ceiling," the quarterly ceiling or the annualized ceiling shall be less than
18.0% per annum or more than 24% per annum, the provisions of Section 303.009(a)
and (b) of the Texas Finance Code, as amended, shall control for purposes of
such determination, as applicable. The Maximum Legal Rate shall be applied by
taking into account all amounts characterized by applicable law as interest on
the indebtedness evidenced by this Note, so that the aggregate of all interest
does not exceed the maximum nonusurious amount permitted by applicable law. The
Maximum Rate shall be calculated in a manner that takes into account any and all
fees, payments, and other charges in respect of the Loan Documents that
constitute interest under applicable law. Each change in any interest rated
provided for herein based upon the Maximum Rate resulting from a change in the
Maximum Rate shall take effect without notice to the Borrower at the time of
such change in the Maximum Rate.

        PAYMENT SCHEDULE. Commencing on January 1, 2005, and continuing
thereafter through the final maturity date hereof, Borrower shall pay to the
holder hereof quarterly installments of all accrued and unpaid interest on this
Note. The entire amount of unpaid principal and interest accrued hereon shall be
due and payable on the first anniversary of this Note.

        APPLICATION OF PAYMENTS; LATE CHARGES. All payments on this Note shall
be applied, first, to the payment of accrued interest and the balance to
principal; provided, however, in the event that the Lender shall have made any
advance in addition to the principal of this Note under the terms of any
instrument evidencing or securing the payment of this Note, any payment
received, at the option of Lender, may first be applied to repay such advances
plus interest thereon. All past due principal and accrued interest on this Note
shall bear interest from maturity until paid at the Maximum Legal Rate, or, if
there is no Maximum Legal Rate, at the rate of eighteen percent (18%) per annum.
Further, at the option of the Lender, Borrower will pay a "late charge" not
exceeding five percent (5%) of any delinquent installment on the Note when such
installment is paid more than five (5) days after the due date thereof,
regardless of whether or not such delinquency shall constitute an Event of
Default (hereinafter defined) hereunder, to cover the extra expenses involved in
handling delinquent payments. If any installment of principal and/or interest on
this Note shall become due on a Saturday, Sunday or any other day on which
Lender is not open for business, such installment shall be paid on the next
succeeding day on which Lender is open for business, and such extension of time
shall in such event be included in computing the amount of interest payable in
connection with such installment.

        EVENTS OF DEFAULT. The occurrence of any one or more of the following
events shall constitute an "EVENT OF DEFAULT" hereunder (whether such occurrence
shall be voluntary or involuntary or come about or be effected by operation of
law or otherwise):

(a)     The Borrower shall fail to make any payment of principal or interest
        upon this Note on the date when due; or

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(b)     The Borrower or the Guarantor (hereinafter defined) shall fail to duly
        observe, perform or comply with any covenant, agreement or term
        contained in this Note or any of the Loan Documents (hereinafter
        defined). The "LOAN DOCUMENTS" shall mean all documents and instruments
        evidencing or securing the Note; or

(c)     Any of the following: (i) the Borrower or the Guarantor shall become
        insolvent or unable to pay its debts as they mature, make an assignment
        for the benefit of creditors' or admit in writing its inability to pay
        its debts generally as they become due or fail generally to pay its
        debts as they mature; or (ii) an order, judgment or decree is entered
        adjudicating the Borrower or the Guarantor insolvent; or, (iii) the
        Borrower or the Guarantor shall petition or apply to any tribunal for
        the appointment of a trustee, receiver, custodian or liquidator of the
        Borrower or the Guarantor or of any substantial part of the assets of
        the Borrower or the Guarantor under any bankruptcy, reorganization,
        compromise, arrangement, insolvency, readjustment of debts, dissolution,
        or liquidation law of any jurisdiction, whether now or hereafter in
        effect; or (iv) any such petition or application shall be filed, or any
        such proceeding shall be commenced, of a type described in subsection
        (iii), above, against the Borrower or the Guarantor, as the case may be,
        by any act shall indicate its approval thereof, consent thereto or
        acquiescence therein, or an order, judgment or decree shall be entered
        appointing any such trustee, receiver, custodian or liquidator, or
        approving the petition in any such proceeding; or (v) any order,
        judgment or decree shall be entered in any proceedings against the
        Borrower decreeing the dissolution of the Borrower and such order,
        judgment or decree shall remain unstayed and in effect for more than
        sixty (60) days; or (vi) any order, judgment or decree shall be entered
        in any proceedings against the Borrower decreeing a split-up of the
        Borrower which requires the divestiture of a substantial part of the
        assets of the Borrower, and such order, judgment or decree shall remain
        unstayed and in effect for more than sixty (60) days; or (vii) the
        Borrower shall fail to make timely payment or deposit of any amount of
        tax required to be withheld by the Borrower and paid to or deposited to
        or to the credit of the United States of America pursuant to the
        provisions of the Internal Revenue Code, in respect of any and all wages
        and salaries paid to employees of the Borrower.

        Upon the occurrence of any Event of Default or other default hereunder
or under any other agreement or instrument securing or assuring the payment of
this Note or executed in connection herewith, the holder hereof may, at its
option, declare the entire unpaid balance of principal and accrued interest on
this Note to be immediately due and payable; provided, however, upon the
occurrence of any of the Events of Default described in clause (c) above, the
entire unpaid balance of principal and accrued interest upon this Note shall,
without any action by Lender, immediately become due and payable without demand
for payment, presentment, protest, notice of protest and non-payment, or other
notice of default, notice of acceleration, note of intention to accelerate or
any other notice, all of which are expressly waived by Borrower.

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        "DEFAULT RATE" shall mean the lesser of (i) the Maximum Rate or (ii) the
Interest Rate in effect from day to day plus four percent (4.0%). After the
occurrence and during the continuation of an Event of Default, the principal of
this Note shall bear interest at the greater of (i) a per annum rate equal to
the Default Rate, or (ii) six percent (6%) per annum.

        CALCULATION OF INTEREST RATE. The books and records of the Lender shall
constitute prima facie evidence of the outstanding principal amount of this Note
and interest accrued in respect thereof. Computation of interest on all amounts
payable by the Borrower hereunder shall be computed on the basis of a year of
360 days and the actual number of days elapsed (including the first day but
excluding the last) unless such calculation would result in a usurious rate, in
which case interest shall be calculated on the basis of a year of 365 or 366
days, as the case may be. Notwithstanding the foregoing, if at any time the
Interest Rate shall exceed the Maximum Rate, thereby causing the interest
payable on this Note to be limited to the Maximum Rate, then any subsequent
reductions in the Interest Rate shall not reduce the rate of interest charged
hereunder below the Maximum Rate until the total amount of interest accrued
hereon from and after the date hereof equals the amount of interest that would
have accrued hereon if the Interest Rate had at all times been in effect.

        GUARANTOR. This Note is secured by a Guaranty Agreement (the
"GUARANTY"), dated of event date herewith, executed by Behringer Harvard REIT I,
Inc. (the "GUARANTOR"). Reference is hereby made to the Guaranty for a
description of the rights of the Lender (or the holder of this Note) and the
Borrower in respect thereof.

        PREPAYMENT. Borrower may prepay the principal hereof, in full or in
part, at any time, without premium or penalty. Upon full payment, this Note
shall be canceled and returned to Borrower.

        WAIVERS; CONSENTS. Except as expressly otherwise provided herein,
Borrower, and all sureties, endorsers, guarantors, and any other party now or
hereafter liable for the payment of this Note, in whole or in part, hereby
jointly and severally waive (to the extent permitted by law) all applicable
exemption rights, whether under the Texas Constitution, homestead laws or
otherwise, and also jointly and severally waive valuation and appraisement,
demand, presentment, protest, notice of non-payment, notice of dishonor, notice
of acceleration, notice of intent to accelerate, notice of protest and any and
all other notices or lack of diligence or delay in collection or the filing of
suit hereon which may occur, and consent to all renewals, extensions, releases,
or substitutions of security, in whole or in part, with or without notice,
before or after maturity hereof and to all partial payments hereon, whether
before or after maturity.

        NO WAIVER OF RIGHTS. No waiver by Lender of any of its rights or
remedies hereunder or under any other document evidencing or securing this Note
or otherwise shall be considered a waiver of any other subsequent right or
remedy of Lender. No delay or omission in the exercise of enforcement by Lender
of any rights or remedies shall ever be construed as a waiver of any right or
remedy of Lender. No exercise or enforcement of any such rights or remedied
shall ever be held to exhaust any right or remedy of Lender.

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        CUMULATIVE RIGHTS. If more than one person or entity executes this Note
as Borrower, or endorses this Note, all of said parties shall be jointly and
severally liable for the repayment of the indebtedness secured hereby. No delay
on the part of the holder of this Note in the exercise of any power or right
under this Note, under the Security Documents, or under any other instrument
executed pursuant hereto, or to evidence, secure or perfect any security for the
payment of this Note, shall operate as a waiver thereof, nor shall a single or
partial exercise of any other power or right. Enforcement by the holder of this
Note of any security for the payment hereof shall not constitute an election by
it of remedies so as to preclude the exercise of any other remedy available to
the holder of this Note.

        NOTICES. All notices or demands required or permitted hereunder shall be
in writing, and shall be deemed to be delivered on actual receipt, if hand
delivered or delivered by courier service, or, whether actually received or not,
three (3) days after the deposit of both the original and the copy, as provided
below, in a regularly maintained receptacle for the mail, registered or
certified mail, return receipt requested, postage prepaid, addressed as follows:

If to Lender:                             Copy To:
------------                              -------

First American Bank, SSB                  Robert M. Allen
One Lincoln Park                          Clements, Allen, Woods & Margolis P.C.
8401 N. Central Expressway, Suite 500     15303 Dallas Parkway, Suite 1050
Dallas, Texas 75225                       Addison, Texas 75001
Attention: Mr. Mike McGee

If to Borrower:
---------------

Behringer Harvard Holdings, LLC
Addison Circle One
15601 Dallas Parkway, Suite 600
Addison, Texas 75001

        Either the Borrower or the Lender may change its respective address or
addressee by giving notice of such change to the other party in the manner
provided herein. For this purpose only, unless and until such written notice if
actually received, the address and addressee specified for each party shall be
deemed to continue in effect for all purposes.

        GOVERNING LAW. This Note has been executed and delivered, and is to be
performed, in the State of Texas, and the laws of such state shall govern the
validity, construction, enforcement and interpretation of this Note; provided,
however, that nothing herein shall limit or impair any right which Lender has
under applicable laws of the United States of America to charge a rate of
interest on sums evidenced by this Note at a rate which exceeds the Maximum
Legal Rate allowed under the laws of the State of Texas. The obligations of the
Borrower under this Note are performable in Dallas County, Texas.

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        HEADINGS. The headings of the sections of this Note are inserted for
convenience only and shall not be deemed to constitute a part hereof.

        LIMITATION OF INTEREST. All agreements between Borrower and Lender are
expressly limited so that in no contingency or event whatsoever whether by
reason of advancement of the proceeds hereof, acceleration of maturity of the
unpaid principal balance hereof, or otherwise, shall the amount paid or agreed
to be paid to the holder hereof for the use, forbearance or detention of the
money to be advanced hereunder exceed the Maximum Legal Rate. If, from any
circumstance whatsoever, fulfillment of any provision hereof or of the Guarantee
or any other agreement referred to herein shall, at the time fulfillment of such
provision be due, involve transcending the limit of validity prescribed by law
which a court of competent jurisdiction may deem applicable hereto, then IPSO
FACTO, the obligation to be fulfilled shall be reduced to the limit of such
validity, and if from any circumstance the holder hereof shall ever receive as
interest an amount which would be excessive interest, such amount shall be
applied to the reduction of the unpaid principal balance due hereunder in the
inverse order of its maturity and not to the payment of interest or, if such
amount which would have been excessive interest exceeds the unpaid principal
hereof, such excess shall be refunded to Borrower. All interest paid or agreed
to be paid to Lender shall, to the extent permitted by applicable law, be
amortized, prorated, allocated and spread throughout the full stated term
(including any renewal or extension) of such indebtedness so that the amount of
interest on account of such indebtedness does not exceed the maximum permitted
by applicable law. This provision shall control every other provision of all
agreements between Borrower and the holder hereof.

        SUCCESSORS AND ASSIGNS. All of the covenants, stipulations, promises and
agreements in this Note contained by or on behalf of Borrower shall bind its
successors and assigns, whether so expressed or not. The words "Lender" and
"Borrower," whenever used in this Note, shall include the respective heirs,
distributees, personal representatives, successors and assigns of Lender and
Borrower.

        ATTORNEY'S FEES. If this Note shall be placed in the hands of an
attorney for collection after an Event of Default shall occur, or should it be
collected in any probate, bankruptcy or other judicial or administrative
proceeding, whether before or after maturity, Borrower agrees to pay a
reasonable sum as attorneys' fees and to pay all other costs of collection
and/or suit.

        "BUSINESS DAY" shall mean a day other than a Saturday, Sunday or a day
upon which banks in the State of Texas are closed to conduct business generally.

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        IN WITNESS WHEREOF, the undersigned has executed this Note as of the day
and year first above written.


                                      BEHRINGER HARVARD HOLDINGS, LLC,
                                      a Delaware limited liability company


                                      By:________________________________
                                      Name:______________________________
                                      Title:_____________________________