ASN Archstone Smith Tr

As filed with the Securities and Exchange Commission on October 5, 2007

Registration No. 333-31031-99

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Post-Effective Amendment No. 2 to

FORM S-8

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

ARCHSTONE-SMITH TRUST

(Exact name of registrant as specified in its charter)

c/o TISHMAN SPEYER ARCHSTONE-SMITH MULTIFAMILY SERIES I TRUST

9200 E. Panorama, Suite 400

Englewood, Colorado 80112

(303) 708-5959

(Address of principal executive offices) (Zip code)

Archstone-Smith Trust Equity Plan for Outside Trustees

(formerly known as the Archstone-Smith Trust 1996 Share Option Plan for Outside Trustees)

(Full title of the plan)

Caroline Brower

Executive Vice President and General Counsel

Tishman Speyer Archstone-Smith Multifamily Series I Trust

9200 E. Panorama, Suite 400

Englewood, Colorado 80112

(303) 708-5959

(Name, address and telephone number, including area code, of agent for service)

TERMINATION OF REGISTRATION

This Post-Effective Amendment No. 2 relates to the Registration Statement on Form S-8 (Registration No. 333-31031-99) of Archstone-Smith Trust, a Maryland real estate investment trust (“ASN”).

On October 5, 2007, pursuant to the terms of the Agreement and Plan of Merger, dated as of May 28, 2007, as amended by Amendment No. 1 thereto, dated as of August 5, 2007, by and among ASN, Archstone-Smith Operating Trust, River Holding, LP, River Acquisition (MD), LP  and River Trust Acquisition (MD), LLC, ASN merged with and into Tishman Speyer Archstone-Smith Multifamily Series I Trust, an assignee of River Acquisition (MD), LP (the “Merger”).

As a result of the consummation of the Merger, ASN’s common shares of beneficial interest, par value $0.01 per share, are no longer publicly traded and a Form 15 to de-register the common shares under the Securities Exchange Act of 1934, as amended, is being contemporaneously filed with the Securities and Exchange Commission. Accordingly, ASN hereby removes from registration all of its securities registered pursuant to this Registration Statement that remain unissued.

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