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                                                                     EXHIBIT 5.1

                  [Letterhead of Morris, Manning & Martin, LLP]

                                September 5, 2001

Manhattan Associates, Inc.
2300 Windy Ridge Parkway, Suite 700
Atlanta, Georgia  30339

         Re:      Registration Statement on Form S-8

Ladies and Gentlemen:

         We have acted as counsel for Manhattan Associates, Inc., a Georgia
corporation (the "Registrant"), in connection with the registration under the
Securities Act of 1933, as amended, pursuant to a Registration Statement on Form
S-8, of a proposed offering of 1,659,453 shares of the Registrant's common
stock, par value $.01 per share (the "Shares") issuable pursuant to the
Manhattan Associates, Inc. 1998 Stock Incentive Plan (the "Plan").

         We have examined and are familiar with the originals or copies
certified or otherwise identified to our satisfaction of such documents,
corporate records, and other instruments relating to the incorporation of the
Registrant and to the authorization and issuance of Shares under the Plan as
would be necessary and advisable for purposes of rendering this opinion. Based
upon and subject to the foregoing, we are of the opinion that the Shares have
been duly authorized and, when issued as contemplated by the Plan, will be
validly issued, fully paid and nonassessable.

         We hereby consent to the filing of this Opinion as Exhibit 5.1 to the
Registrant's registration statement on Form S-8.

                                          Very truly yours,

                                          MORRIS, MANNING & MARTIN, LLP



                                          /s/ Morris, Manning & Martin, LLP