SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

                                 SCHEDULE 13G


                                 (Rule 13d-102)


             INFORMATION STATEMENT PURSUANT TO RULES 13d-1 AND 13d-2


                   Under the Securities Exchange Act of 1934
                               (Amendment No. 3)


                            AVALONBAY COMMUNITIES INC
             -----------------------------------------------------
                                (Name of Issuer)
                                  Common Stock
              -----------------------------------------------------
                         (Title of Class of Securities)

                                   053484101
             -----------------------------------------------------
                                 (CUSIP Number)



Check the following box if a fee is being paid with this statement [].


----------
*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).



CUSIP No. 053484101            13G                    Page 2  of 8 Pages



--------------------------------------------------------------------------------
   1.  NAME OF REPORTING PERSON(S)
       S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON(S)

       Morgan  Stanley
       IRS  #  39-314-5972
--------------------------------------------------------------------------------
   2.  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
                                                             (a)  [  ]
                                                             (b)  [  ]

--------------------------------------------------------------------------------
   3.  SEC USE ONLY


--------------------------------------------------------------------------------
   4.  CITIZENSHIP OR PLACE OF ORGANIZATION

       The state of organization is Delaware.
--------------------------------------------------------------------------------
   NUMBER OF      5.   SOLE VOTING POWER
     SHARES            0
  BENEFICIALLY    --------------------------------------------------------------
    OWNED BY      6.   SHARED VOTING POWER
      EACH             4,536,707
   REPORTING      --------------------------------------------------------------
     PERSON       7.   SOLE DISPOSITIVE POWER
      WITH             0
                  --------------------------------------------------------------
                  8.   SHARED DISPOSITIVE POWER
                       4,536,707
--------------------------------------------------------------------------------
   9.  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

       6,070,166
--------------------------------------------------------------------------------
  10.  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*


--------------------------------------------------------------------------------
  11.  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

       8.56%
--------------------------------------------------------------------------------
  12.  TYPE OF REPORTING PERSON*

       IA,  CO
--------------------------------------------------------------------------------
                     *SEE INSTRUCTIONS BEFORE FILLING OUT!


CUSIP No. 053484101            13G                    Page 3  of  8  Pages

--------------------------------------------------------------------------------
   1.  NAME OF REPORTING PERSON(S)
       S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON(S)

       Morgan Stanley Investment Management Inc.
       IRS  #  13-3040307
--------------------------------------------------------------------------------
   2.  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
                                                             (a)  [  ]
                                                             (b)  [  ]
--------------------------------------------------------------------------------
   3.  SEC USE ONLY


--------------------------------------------------------------------------------
   4.  CITIZENSHIP OR PLACE OF ORGANIZATION

       The state of organization is Delaware.
--------------------------------------------------------------------------------
   NUMBER OF      5.   SOLE VOTING POWER
     SHARES             0
  BENEFICIALLY    --------------------------------------------------------------
    OWNED BY      6.   SHARED VOTING POWER
      EACH             3,983,889
   REPORTING      --------------------------------------------------------------
     PERSON       7.   SOLE DISPOSITIVE POWER
      WITH              0
                  --------------------------------------------------------------
                  8.   SHARED DISPOSITIVE POWER
                       3,983,889
--------------------------------------------------------------------------------
   9.  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

       5,385,548
--------------------------------------------------------------------------------
  10.  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

--------------------------------------------------------------------------------
  11.  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

       7.61%
--------------------------------------------------------------------------------
  12.  TYPE OF REPORTING PERSON*

       IA, CO
--------------------------------------------------------------------------------
                     *SEE INSTRUCTIONS BEFORE FILLING OUT!



CUSIP No. 053484101                13G                   Page 4  of 8 Pages


Item 1.     (a)   Name of Issuer:
                  AVALONBAY COMMUNITIES INC
                  --------------------------------------------------------------
            (b)   Address of Issuer's Principal Executive Offices:
                  2900 EISENHOWER AVENUE
                  SUITE 300
                  ALEXANDRIA, VA 22314
                  --------------------------------------------------------------
Item 2.     (a)   Name of Person Filing:
                  (a) Morgan Stanley
                  (b) Morgan Stanley Investment Management Inc.
                  --------------------------------------------------------------
            (b)   Address of Principal Business Office, or if None, Residence:

                  (a) 1585 Broadway
                      New York, New York 10036

                  (b) 1221 Avenue of the Americas
                      New York, New York 10020
                  --------------------------------------------------------------
            (c)   Citizenship:

                  Incorporated by reference to Item 4 of the
                  cover page pertaining to each reporting person.
                  --------------------------------------------------------------

            (d)   Title of Class of Securities:
                  Common Stock
                  --------------------------------------------------------------
            (e)   CUSIP Number:
                  053484101
                  --------------------------------------------------------------

Item 3.     (a)   Morgan Stanley is a parent holding company.

            (b)   Morgan Stanley Investment Management Inc. is
                  an Investment Adviser registered under Section 203 of the
                  Investment Advisers Act of 1940.




CUSIP No. 053484101                13-G                   Page 5  of  8  Pages



Item 4.     Ownership.

            Incorporated by reference to Items (5) - (9) and (11) of the
            cover page.

Item 5.     Ownership of Five Percent or Less of a Class.

            Inapplicable

Item 6.     Ownership of More Than Five Percent on Behalf of Another Person.

            Accounts managed on a discretionary basis by Morgan Stanley
            Investment Management Inc., a wholly owned subsidiary of
            Morgan Stanley, are known to have the right to
            receive or the power to direct the receipt of dividends from, or
            the proceeds from, the sale of such securities.  No such account
            holds more than 5 percent of the class.

Item 7.     Identification and Classification of the Subsidiary which Acquired
            the Security Being Reported on By the Parent Holding Company.

Item 8.     Identification and Classification of Members of the Group.

Item 9.     Notice of Dissolution of Group.

Item 10.    Certification.

            By signing below I certify that, to the best of my knowledge and
            belief, the securities referred to above were acquired in the
            ordinary course of business and were not acquired for the purpose
            of and do not have the effect of changing or influencing  the
            control of the issuer of such securities and were not acquired in
            connection with or as a participant in any transaction having
            such purpose or effect.


CUSIP No. 053484101               13-G                   Page 6  of  8 Pages


                                  Signature.


            After reasonable inquiry and to the best of my  knowledge and
            belief, I certify that the information set forth in this
            statement is true, complete and correct.


Date:       February 15, 2004


Signature:  /s/ Dennine Bullard
            -----------------------------------------------------------------

Name/Title  Dennine Bullard /Vice President, Morgan Stanley & Co. Incorporated
            -----------------------------------------------------------------
            MORGAN STANLEY

Date:       February 15, 2004

Signature:  /s/ Jeffrey Hiller
            -----------------------------------------------------------------

Name/Title  Jeffrey Hiller /Managing Director, Morgan Stanley Investment
                             Management Inc.
            -----------------------------------------------------------------
            MORGAN STANLEY INVESTMENT MANAGEMENT INC.

                      INDEX TO EXHIBITS                             PAGE
                      -----------------                             ----

EXHIBIT 1       Agreement to Make a Joint Filing                       7

EXHIBIT 2       Secretary's Certificate Authorizing Dennine Bullard    8
                to Sign on behalf of Morgan Stanley


               *  Attention.  Intentional misstatements or omissions of fact
               constitute federal criminal violations (see 18 U.S.C. 1001).

(022597DTI)

                   EX-99
            JOINT FILING AGREEMENT



CUSIP No. 053484101              13-G                   Page 7  of  8 Pages


                            EXHIBIT 1 TO SCHEDULE 13G
               ---------------------------------------------------


                              FEBRUARY 15, 2004
               ---------------------------------------------------


            MORGAN STANLEY and MORGAN STANLEY INVESTMENT MANAGEMENT

            INC. hereby agree that, unless differentiated, this Schedule

            13G is filed on behalf of each of the parties.


            MORGAN STANLEY

            BY: /s/ Dennine Bullard
            --------------------------------------------------------------------
            Dennine Bullard /Vice President, Morgan Stanley & Co. Incorporated

            MORGAN STANLEY INVESTMENT MANAGEMENT INC.

            BY: /s/ Jeffrey Hiller
            --------------------------------------------------------------------
            Jeffrey Hiller /Managing Director, Morgan Stanley Investment
                            Management Inc.


* Attention. Intentional misstatements or omissions of fact constitute federal
  criminal violations (see 18 U.S.C. 1001).


                   EX-99
              SECRETARY'S CERTIFICATE



 CUSIP No. 053484101                                         Page 8 of 8 pages
                                  EXHIBIT 2

                               MORGAN STANLEY

                           SECRETARY'S CERTIFICATE


         I, Charlene R. Herzer,  a duly elected and Assistant Secretary
         of Morgan Stanley, a corporation  organized and
         existing under the laws of the State of Delaware (the
         "Corporation"), certify as follows:


             (1) Donald G. Kempf, Jr. is the duly elected Executive Vice
                 President, Chief Legal Officer and Secretary of the
                 Corporation;

             (2) Pursuant to Section 7.01 of the Bylaws of the Corporation
                 and resolutions approved by the Board of Directors of the
                 Corporation on September 25,1998, the Chief Legal Officer
                 is authorized to enter into agreements and other instruments
                 on behalf of the Corporation and may delegate such powers
                 to others under his jurisdiction; and

             (3) Donald G. Kempf signed a Delegation of Authority as of
                 February 23, 2000, which authorized Dennine Bullard to
                 sign reports to be filed under Section 13 and 16 of the
                 Securities Exchange Act of 1934 on behalf of the
                 Corporation.  Such authorization is in full force and
                 efect as of this date.

          IN WITNESS WHEREOF, I have hereunto set my name and affixed the seal
          of the Corporation as of the 5th day of February, 2003.

                                                ______________________________
                                                Charlene R. Herzer
                                                Assistant Secretary