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                    Active Assets Institutional Money Trust
            Active Assets Institutional Government Securities Trust

                          1221 Avenue of the Americas
                            New York, New York 10020

October 27, 2006

Securities and Exchange Commission
Judiciary Plaza
100 F Street, NE
Washington, D.C.  20549
Attention: Larry Greene


 Re:  ACTIVE ASSETS INSTITUTIONAL MONEY TRUST
      Post-Effective Amendment No. 8 to the Fund's Registration Statement
      (File Nos. 333-91725 and 811-9713 and Accession No. 0001047469-06-011341)

      ACTIVE ASSETS INSTITUTIONAL GOVERNMENT SECURITIES TRUST
      Post-Effective Amendment No. 5 to the Fund's Registration Statement
      (File Nos. 333-81184 and 811-21024 and Accession No. 0001047469-06-011340)

      (individually, the "Fund" and collectively, the "Funds")


Dear Mr. Greene:

     Pursuant to Rule 477 of the Securities Act of 1933, as amended (the "Act"),
the Funds hereby submit this application for withdrawal of the above referenced
filings, as filed with the Securities and Exchange Commission (the "Commission")
on August 28, 2006 (the "Amendment(s)"). The Amendments were filed pursuant to
Rule 485(a) of the Act and were scheduled to become automatically effective on
October 31, 2006. No securities have been sold in connection with these
Amendments.

     These Amendments were filed pursuant to Rule 485(a) under the Act in
connection with making certain material changes to each Fund's Registration
Statements on Form N-1A, which changes were contingent on the receipt of
shareholder approval to modify certain of the Funds' fundamental investment
restrictions. These Amendments are being withdrawn as the Funds have yet to
obtain a quorum necessary to hold meetings with respect to the proposed modified
investment restrictions. These Funds have adjourned their shareholder meetings
and hope to obtain a quorum and have shareholders approve the modified
investment restrictions at the adjourned meeting. If shareholders approve these
modified investment policies at the adjourned meeting, these Funds intend to
file an amendment pursuant to Rule 485(a) of the Act in connection with its next
"annual update" reflecting the modified investment policies.

     These Funds respectfully requests that this application to withdraw the
Amendment be approved by the Commission as soon as possible.

     If you have any questions, please do not hesitate to contact the
undersigned at 212-762-5198.


                                                     Respectfully,


                                                     /s/ Joanne Doldo
                                                     ---------------------------
                                                     Joanne Doldo