ERP OPERATING LIMITED PARTNERSHIP (an Illinois limited partnership) $500,000,000 5.25% Notes due 2014 TERMS AGREEMENT

Exhibit 1

ERP OPERATING LIMITED PARTNERSHIP

(an Illinois limited partnership)

$500,000,000  5.25% Notes due 2014

TERMS AGREEMENT

Dated:  September 9, 2004

To: ERP Operating Limited Partnership

c/o Equity Residential

Xxx Xxxxx Xxxxxxxxx Xxxxx

Xxxxxxx, Xxxxxxxx 00000

Attention: Xxxxx X. Xxxxxxxxxx

Ladies and Gentlemen:

We (the “Representatives”) understand that ERP Operating Limited Partnership, an Illinois limited partnership (“ERP”), proposes to issue and sell $500,000,000 aggregate principal amount of 5.25% Notes due 2014 (the “Underwritten Securities”).  Subject to the terms and conditions set forth or incorporated by reference herein, the Underwriters named below (the “Underwriters”) severally, and not jointly, agree to purchase the respective amounts of the Underwritten Securities set forth below opposite their respective names, at the purchase price set forth below.

Underwriter		Principal Amount of Underwritten Securities
Banc of America Securities LLC		$	197,500,000
Wachovia Capital Markets, LLC		197,500,000
BNY Capital Markets, Inc.		30,000,000
Commerzbank Capital Markets Corp.		30,000,000
Xxxxx Xxxxxxx & Co.		30,000,000
Wedbush Xxxxxx Securities Inc.		15,000,000
Total		$	500,000,000

The Underwritten Securities shall have the following terms:

Title:		5.25% Notes due 2014
Principal Amount to be Issued:		$500,000,000
Currency:		U.S. Dollars
Current Ratings:		Baa1 by Xxxxx’x Investors Services, Inc. BBB+ by Standard & Poor’s Ratings Services A- by Fitch Investor Services

Form:		Registered book-entry form
Price to Public:		99.877% of the principal amount of the Underwritten Securities
Purchase Price:		99.227% of the principal amount of the Underwritten Securities
Stated Maturity Date:		September 15, 2014
Interest Rate:		5.25% per annum
Interest Payment Dates:		Interest on the Underwritten Securities will be payable semi-annually in arrears, on September 15 and March 15 of each year, beginning March 15, 2005
Record Dates:		The close of business on the March 1 and September 1 preceding the applicable Interest Payment Date
Redemption:		ERP may redeem the Underwritten Securities, at any time, in whole or, from time to time, in part, at the election of ERP, at a redemption price equal to the sum of (i) the principal amount of the Underwritten Securities being redeemed plus accrued interest thereon to the redemption date and (ii) the Make-Whole Amount (as defined in the Prospectus relating to such Underwritten Securities), if any, with respect to such Underwritten Securities (collectively, the “Redemption Price”).  Notice of any optional redemption of any Underwritten Securities will be given to holders at their addresses, as shown in the Security Register, not more than 60 nor less than 30 days prior to the date fixed for redemption.  The notice of redemption will specify, among other items, the Redemption Price and the principal amount of the Underwritten Securities held by such persons to be redeemed
Reinvestment Rate:		“Reinvestment Rate” means .20% plus the arithmetic means of the yields under the respective heading “Week Ending” published in the most recent Statistical Release (as defined in the Prospectus relating to such Underwritten Securities) under the caption “Treasury Constant Maturities” for the maturity (rounded to the nearest month) corresponding to the remaining life to maturity, as of the payment date of the principal being redeemed or paid. If no maturity exactly corresponds to such maturity, yields for the two published maturities most closely corresponding to such maturity shall be calculated pursuant to the immediately preceding sentence and the Reinvestment Rate shall be interpolated or extrapolated from such yields on a straight-line basis, rounding in each of such relevant periods to the nearest month. For the purposes of calculating the Reinvestment Rate, the most recent Statistical Release published prior to the date of determination of the Make-Whole Amount shall be used
Sinking Fund Requirements:		None

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Listing:		None
Delayed Contracts:		Not authorized
Restrictive Covenants:		The covenants set forth in Article Two of the First Supplemental Indenture, dated September 9, 2004, to the Indenture, dated October 1, 1994, between ERP and X.X. Xxxxxx Trust Company, National Association
Settlement Date, Time and Place:		Delivery of documents on September 14, 2004, at 9:00 a.m. New York City time at the offices of Xxxxx & Xxxxxxx L.L.P., 000 Xxxxxxxxxx Xxxxxx, X.X., Xxxxxxxxxx, X.X. 00000; delivery of funds on September 14, 2004, in accordance with DTC procedures for the Underwritten Securities

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All the provisions contained in the document attached as Annex A hereto entitled “ERP Operating Limited Partnership—Debt Securities—Standard Underwriting Provisions” are hereby incorporated by reference in their entirety herein and shall be deemed to be a part of this Terms Agreement to the same extent as if such provisions had been set forth in full herein.  Terms defined in such document are used herein as therein defined.

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Please accept this offer no later than 6:00 P.M. (New York City time) on September 9, 2004, by signing a copy of this Terms Agreement in the space set forth below and returning the signed copy to us.

				Very truly yours
				BANC OF AMERICA SECURITIES LLC
				By:	/s/ Xxxx Xxxxx
						Name:  Xxxx Xxxxx
						Title:  Principal
				WACHOVIA CAPITAL MARKETS, LLC
				By:	/s/ Xxx Xxxxxxxxxx
						Name:  Xxx Xxxxxxxxxx
						Title:  Managing Director
				acting on behalf of themselves and the other named Underwriters
Accepted:
ERP OPERATING LIMITED PARTNERSHIP
By:  EQUITY RESIDENTIAL, not individually but as General
Partner
	By:	/s/ Xxxxx X. Xxxxxx
			Name: Xxxxx X. Xxxxxx
			Title: Executive Vice President & General Counsel

Annex A