Erp Operating LTD Partnership 8-K Other Events

Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

We consent to the incorporation by reference in the Registration Statements (Form S-3 No. 333-105850 and Forms S-4 No. 333-44576 and No. 333-36053) of ERP Operating Limited Partnership and in the related Prospectuses of our report dated February 28, 2006 (except for the fourth paragraph of Note 21, for which the date is March 2, 2006 and Notes 12, 13 and 20, for which the date is May 22, 2006), with respect to the consolidated financial statements and schedule of ERP Operating Limited Partnership, included in this Current Report on Form 8-K.

	/s/ Ernst & Young LLP
	Ernst & Young LLP
Chicago, Illinois
May 22, 2006

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