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                                                                   Exhibit 10.80

                             SECURED PROMISSORY NOTE
                                LOAN NO. 753864

$12,700,000.00                                                    March 26, 2004

     1.   FOR VALUE RECEIVED, INLAND WESTERN IRVING LIMITED PARTNERSHIP, an
Illinois limited partnership, as "BORROWER" ("Borrower" to be construed as
"Borrowers" if the context so requires), hereby promises to pay to the order of
PRINCIPAL LIFE INSURANCE COMPANY, an Iowa corporation (as "LENDER"), having a
principal place of business and post office address at c/o Principal Real Estate
Investors, LLC, 801 Grand Avenue, Des Moines, Iowa 50392-1450, or at such other
place as Lender may designate, the principal sum of Twelve Million Seven Hundred
Thousand and 00/100 Dollars ($12,700,000.00) (the "LOAN AMOUNT") or so much
thereof as shall from time to time have been advanced, together with interest on
the unpaid balance of said sum from April 2, 2004 (the "CLOSING DATE"), at the
lesser of (a) the maximum rate permitted by applicable law and (b) prior to
default or maturity, the rate of four and 29/100 percent (4.29%) per annum.

     A payment of interest from the Closing Date to and including April 30,
2004, shall be paid on the Closing Date calculated by multiplying the actual
number of days elapsed in the period for which interest is being calculated by a
daily rate based on the foregoing annual interest rate and a 360-day year.
Thereafter, interest shall be computed on the unpaid balance on the basis of a
360-day year composed of twelve 30-day months. Beginning on June 1, 2004,
interest shall be due and payable in arrears in monthly installments of
Forty-five Thousand Four Hundred Two and 50/100 Dollars ($45,402.50), with an
installment in a like amount due and payable on the same day of each month
thereafter, except that all remaining principal and interest to and including
the date of payment and other Indebtedness shall be due and payable on May 1,
2009 or such earlier date resulting from the acceleration of the Indebtedness by
Lender ("MATURITY DATE"). All principal and interest shall be paid in lawful
money of the United States of America by wire transfer of immediately available
funds to Lender at Wells Fargo Bank, Iowa, N.A., 7th and Walnut Streets, Des
Moines, Iowa 50304, for credit to Principal Life Insurance Company, Account No.
0000014752, RE: Loan No. 753864 with reference to Borrower. In the event
Borrower fails to make any monthly payment under this Note on or before the due
date thereof, Borrower agrees to make all subsequent payments by automated
clearing house transfer through such bank or financial institution as shall be
approved in writing by Lender, shall be made to an account designated by Lender,
and shall be initiated by Lender or shall be made in such other manner as Lender
may direct from time to time. Any other monthly deposits or payments Borrower is
required to make to Lender under the terms of the Loan Documents shall be made
by the same payment method and on the same date as the installments of interest
due under this Note.

     2.   No privilege is reserved by Borrower to prepay any principal of this
Note prior to the Maturity Date, except on or after the date hereof, privilege
is reserved, after giving thirty (30) days' prior written notice to Lender, to
prepay in full, but not in part, all principal and interest to and including the
date on which payment is made, along with all sums, amounts, advances, or
charges due under any instrument or agreement by which this Note is secured,
upon the payment of a "MAKE WHOLE PREMIUM." The Make Whole Premium shall be the
lesser of: (a) the maximum amount which is allowable under Texas law limiting
the amount of interest which may

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be contracted for, charged or received after considering all other amounts
constituting or deemed to constitute interest, and (b) the greater of one
percent (1%) of the principal amount to be prepaid or a premium calculated as
provided in subparagraphs (a) through (c) below:

     (a)  Determine the "REINVESTMENT YIELD." The Reinvestment Yield will be
          equal to the yield on the U.S. Treasury Issue ("PRIMARY ISSUE")*
          published one week prior to the date of prepayment and converted to an
          equivalent monthly compounded nominal yield.

          *At this time there is not a U.S. Treasury Issue for this prepayment
          period. At the time of prepayment, Lender shall select in its sole and
          absolute discretion a U.S. Treasury Issue with similar remaining time
          to maturity as this Note.

     (b)  Calculate the "PRESENT VALUE OF THE LOAN." The Present Value of the
          Loan is the present value of the payments to be made in accordance
          with this Note (all installment payments and any remaining payment due
          on the Maturity Date) discounted at the Reinvestment Yield for the
          number of months remaining from the date of prepayment to the Maturity
          Date.

     (c)  Subtract the amount of the prepaid proceeds from the Present Value of
          the Loan as of the date of prepayment. Any resulting positive
          differential shall be the premium.

If Borrower has otherwise fully complied with the preceding paragraphs, then,
during the last 90 days prior to the Maturity Date, provided no Event of Default
exists, no Make Whole Premium shall be payable.

     3.   Borrower agrees that if Lender accelerates the whole or any part of
the principal sum evidenced hereby, after the occurrence of an Event of Default,
or applies any proceeds pursuant to the provisions of the Loan Documents,
Borrower waives any right to prepay said principal sum in whole or in part
without premium and agrees to pay, as yield maintenance protection and not as a
penalty, the Make Whole Premium.

Notwithstanding the above, in the event any proceeds from a casualty or Taking
of the Premises are applied to reduce the principal balance hereof, such
reduction shall be made without a Make Whole Premium, provided no Event of
Default then exists under the Loan Documents.

     4.   If any payment of principal, interest, Make Whole Premium, or other
Indebtedness is not made when due, damages will be incurred by Lender, including
additional expense in handling overdue payments, the amount of which is
difficult and impractical to ascertain. Borrower therefore agrees to pay, upon
demand, the sum of four cents ($.04) for each one dollar ($1.00) of each said
payment which becomes overdue ("LATE CHARGE") as a reasonable estimate of the
amount of said damages, subject, however, to the limitations contained in
paragraph 6 hereof.

Notwithstanding anything hereinabove to the contrary, the Late Charge assessed
on any amount due on the Maturity Date but not then paid, whether or not by
acceleration, shall not be four cents for each one dollar as described above,
but shall instead be a sum equal to the interest

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which would have accrued on the principal balance then outstanding from the date
the payment is made to the end of the month in which the Maturity Date occurs.
Such Late Charge shall be in addition to interest otherwise accruing under this
Note.

     5.   If any Event of Default has occurred and is continuing under the Loan
Documents, the entire principal balance of the Loan, interest then accrued, and
Make Whole Premium, and all other Indebtedness whether or not otherwise then
due, shall at the option of Lender, become immediately due and payable without
demand or notice, and whether or not Lender has exercised said option, interest
shall accrue on the entire principal balance, interest then accrued, Make Whole
Premium and any other Indebtedness then due, at a rate equal to the Default Rate
until fully paid.

     6.   Notwithstanding anything herein or in any of the other Loan Documents
to the contrary, no provision contained herein or therein which purports to
obligate Borrower to pay any amount of interest or any fees, costs or expenses
which are in excess of the maximum permitted by applicable law, shall be
effective to the extent it calls for the payment of any interest or other amount
in excess of such maximum. All agreements between Borrower and Lender, whether
now existing or hereafter arising and whether written or oral, are hereby
limited so that in no contingency, whether by reason of demand for payment or
acceleration of the maturity hereof or otherwise, shall the interest contracted
for, charged or received by Lender exceed the maximum amount permissible under
applicable law. If, from any circumstance whatsoever, interest would otherwise
be payable to Lender in excess of the maximum lawful amount, the interest
payable to Lender shall be reduced to the maximum amount permitted under
applicable law; and if from any circumstance Lender shall ever receive anything
of value deemed interest by applicable law in excess of the maximum lawful
amount, an amount equal to any excessive interest shall, at the option of
Lender, be refunded to Borrower or be applied to the reduction of the principal
hereof, without a Make Whole Premium and not to the payment of interest or, if
such excessive interest exceeds the unpaid balance of 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 period until payment in full of the
principal (including the period of any renewal or extension hereof) so that the
interest herein for such full period shall not exceed the maximum amount
permitted by applicable law. This paragraph shall control all agreements between
Borrower and Lender.

     7.   Borrower and any endorsers or guarantors waive presentment, protest
and demand, notice of protest, demand and dishonor and nonpayment, and notice of
default, notice of intent to accelerate maturity, notice of acceleration and
maturity, and agree the Maturity Date of this Note or any installment may be
extended without affecting any liability hereunder, and further promise to pay
all reasonable costs and expenses, including but not limited to, reasonable
attorney's fees incurred by Lender in connection with any default or in any
proceeding to interpret and/or enforce any provision of the Loan Documents. No
release of Borrower from liability hereunder shall release any other maker,
endorser or guarantor hereof.

     8.   This Note is secured by the Loan Documents creating among other things
legal and valid encumbrances on and an assignment of all of Borrower's interest
in any Leases of the Premises located in the county of Dallas, state of Texas.
Capitalized terms used herein and not

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otherwise defined shall have those meanings given to them in the Loan Documents.
In no event shall such documents be construed inconsistently with the terms of
this Note, and in the event of any discrepancy between any such documents and
this Note, the terms hereof shall govern. The proceeds of this Note are to be
used for business, commercial, investment or other similar purposes, and no
portion thereof will be used for any personal, family or household use. This
Note shall be governed by and construed in accordance with the laws of the State
where the Premises is located, without regard to its conflict of law principles.

     9.   Notwithstanding any provision to the contrary in this Note or the Loan
Documents and except as otherwise provided for below, the liability of Borrower
and any general partner of Borrower under the Loan Documents shall be limited to
the interest of Borrower and any general partner of Borrower in the Premises and
the Rents. In the event of foreclosure of the liens evidenced by the Loan
Documents, no judgment for any deficiency upon the Indebtedness evidenced by the
Loan Documents shall be sought or obtained by Lender against Borrower or any
general partner of Borrower. Nothing herein shall in any manner limit or impair
(i) the lien or enforcement of the Loan Documents pursuant to the terms thereof
or (ii) the obligations of any indemnitor or guarantor, if any.

     Notwithstanding any provision hereinabove to the contrary, Borrower and any
general partner of Borrower shall be personally liable to Lender for:

     (a)  any loss or damage to Lender arising from (i) the sale or forfeiture
          of the Premises resulting from Borrower's failure to pay any of the
          taxes, assessments or charges specified in the Loan Documents or (ii)
          Borrower's failure to insure the Premises in compliance with the
          provisions of the Loan Documents;

     (b)  any event or circumstance for which Borrower indemnifies Lender under
          the Environmental Indemnity;

     (c)  nonpayment of taxes, assessments, insurance premiums and utilities for
          the Premises and any penalty or late charge associated with nonpayment
          thereof;

     (d)  material failure to manage, operate, and maintain the Premises in a
          commercially reasonable manner for similar property types in the
          surrounding geographic area;

     (e)  any sums expended by Lender in fulfilling the obligations of Borrower
          as lessor under any Lease of the Premises prior to a sale of the
          Premises pursuant to foreclosure or power of sale, a bona fide sale
          (permitted by the terms of paragraph 2(f) of the Deed of Trust (it
          being agreed that "Deed of Trust" as used herein shall be construed to
          mean "mortgage" or "deed of trust" or "trust deed" as the context so
          requires) or consented to in writing by Lender) to an unrelated third
          party or upon conveyance to Lender of the Premises by a deed
          acceptable to Lender in form and content (each of which shall be
          referred to as a "SALE" for purposes of this paragraph) or expended by
          Lender after a Sale of the Premises for obligations of Borrower which
          arose prior to a Sale of the Premises;

          Borrower's personal liability for items specified in (c), (d) and (e)
          above shall be limited to the amount of rents, issues, proceeds and
          profits from the Premises

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          ("RENTS AND PROFITS") received by Borrower for the twenty-four (24)
          months preceding an Event of Default and thereafter; but less any such
          Rents and Profits applied to (A) payment of principal, interest and
          other charges when due under the Loan Documents, or (B) payment of
          expenses for the operation, maintenance, taxes, assessments, utility
          charges and insurance of the Premises including sufficient reserves
          for the same or replacements or renewals thereof ("OPERATION
          EXPENSE(S)") provided that (x) Borrower has furnished Lender with
          evidence satisfactory to Lender of the Operation Expenses and payment
          thereof, and (y) any payments to parties related to Borrower shall be
          considered an Operation Expense only to the extent that the amount
          expended for the Operation Expense does not exceed the then current
          market rate for such Operation Expense.

     (f)  any rents or other income regardless of type or source of payment or
          other considerations in lieu thereof (including, but not limited to,
          common area maintenance charges, lease termination payments, refunds
          of any type, prepayment of rents, settlements of litigation, or
          settlements of past due rents) from the Premises which Borrower has
          received or will receive after an Event of Default under the Loan
          Documents which are not applied to (A) payment of principal, interest
          and other charges when due under the Loan Documents or (B) payment of
          Operation Expenses provided that (x) Borrower has furnished Lender
          with evidence reasonably satisfactory to Lender of the Operation
          Expenses and payment thereof, and (y) any payments to parties related
          to Borrower shall be considered an Operation Expense only to the
          extent that the amount expended for the Operation Expense does not
          exceed the then current market rate for such Operation Expense;

     (g)  any security deposits of tenants not otherwise applied in accordance
          with the terms of the Lease(s), together with any interest on such
          security deposits required by law or the leases, not turned over to
          Lender upon conveyance of the Premises to Lender pursuant to
          foreclosure or power of sale or by a deed acceptable to Lender in form
          and content;

     (h)  misapplication or misappropriation of tax reserve accounts, tenant
          improvement reserve accounts, security deposits, prepaid rents or
          other similar sums paid to or held by Borrower or any other entity or
          person in connection with the operation of the Premises;

     (i)  any insurance or condemnation proceeds or other similar funds or
          payments applied by Borrower in a manner other than as expressly
          provided in the Loan Documents; and

     (j)  any loss or damage to Lender arising from any fraud or willful
          misrepresentation by or on behalf of Borrower, Interest Owner or any
          guarantor regarding the Premises, the making or delivery of any of the
          Loan Documents or in any materials or information provided by or on
          behalf of Borrower, Interest Owner or guarantor, if any, in connection
          with the Loan.

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          Notwithstanding anything contained in paragraphs 9(a)(i) and 9(c)
     hereinabove as it relates solely to taxes, assessments and insurance
     premiums, to the extent Lender is impounding for taxes, assessments and
     insurance premiums in accordance with the Loan Documents and Borrower has
     fully complied with all terms and conditions of the Loan Documents relating
     to impounding for the same, then Borrower shall not be personally liable
     for Lender's failure to apply any of said impound amounts held by Lender in
     accordance with the Loan Documents.

     Notwithstanding anything to the contrary in the Loan Documents, the
limitation on liability contained in the first paragraph of this paragraph 9
SHALL BECOME NULL AND VOID and shall be of no further force and effect in the
event of any breach or violation of paragraph 2(f) (due on sale or encumbrance)
of the Deed of Trust, other than (i) the filing of a nonmaterial mechanic's lien
affecting the Premises or a mechanic's lien affecting the Premises for which
Borrower has complied with the provisions of paragraph l(e) of the Deed of
Trust, or (ii) the granting of any utility or other nonmaterial easement or
servitude burdening the Premises, or (iii) any transfer or encumbrance of a
nonmaterial economic interest in the Premises not otherwise set forth in (i) or
(ii).

     10.  If more than one, all obligations and agreements of Borrower and of
any general partners of Borrower are joint and several.

     11.  This Note may not be changed or terminated orally, but only by
an-agreement in writing and signed by the party against whom enforcement of any
waiver, change, modification or discharge is sought. All of the rights,
privileges and obligations hereunder shall inure to the benefit of the heirs,
successors and assigns of Lender and shall bind the heirs and permitted
successors and assigns of Borrower.

     12.  If any provision of this Note shall, for any reason, be held to be
invalid or unenforceable, such invalidity or unenforceability shall not affect
any other provision hereof, but this Note shall be construed as if such invalid
or unenforceable provision had never been contained herein.

     13.  This Note may be executed in counterparts, each of which shall be
deemed an original; and such counterparts when taken together shall constitute
but one agreement.

     IN WITNESS WHEREOF, Borrower has caused this Note to be duly executed and
delivered as of the date first set forth above.

        (REMAINDER OF PAGE INTENTIONALLY BLANK; SIGNATURES ON NEXT PAGE)

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                     SIGNATURE PAGE OF BORROWER TO
                        SECURED PROMISSORY NOTE


                            INLAND WESTERN IRVING LIMITED
                            PARTNERSHIP, an Illinois limited partnership

                            By:  INLAND WESTERN IRVING GP, L.L.C., a
                                 Delaware limited liability company, its General
                                 Partner

                                 By:  INLAND WESTERN RETAIL REAL
                                      ESTATE TRUST, INC., a Maryland
                                      corporation, its Sole Member


                                      By:   /s/ Valerie Medina
                                            ---------------------------------
                                            Name: Valerie Medina
                                                 ----------------------------
                                            Title: Asst. Secretary
                                                  ---------------------------