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                                                                  EXHIBIT 10.10


                   ASSUMPTION AND ACKNOWLEDGEMENT AGREEMENT


     THIS ASSUMPTION AND ACKNOWLEDGEMENT AGREEMENT, dated this 27th day of
June, 1996, by and between The Dun & Bradstreet Corporation, a Delaware 
corporation (the "Transferor") and ACNielsen Corporation, a Delaware 
corporation (the "Transferee") to and for the benefit of Manugistics Group,
Inc., a Delaware corporation (the "Company").

                                  BACKGROUND


     Pursuant to an agreement dated as of July 26, 1994 (the "Stock Purchase
Agreement") between the Transferor and the Company, the Transferor acquired
490,000 shares of Common Stock of the Company (the "Investor Shares");

     The Transferor desires to transfer all of the Investor Shares to the
Transferee prior to October 1, 1996 (the "Transfer");
     
     The Transferee is an Affiliate of the Transferor, as that term is defined
in the Stock Purchase Agreement; and

     Pursuant to Section 8(e) of the Stock Purchase Agreement, the Transferee
must agree to be bound by Section 8 of the Stock Purchase Agreement as a
condition to the passage of voting rights in respect of the Investor Shares to
the Transferee.

     NOW, THEREFORE, in consideration of the mutual agreements contained
herein, and for other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the parties, intending to be
legally bound, hereby acknowledge, covenant and agree as follows:

     1.  Capitalized terms used herein and not otherwise defined shall have the
meanings ascribed to them in the Stock Purchase Agreement.

     2.  Immediately upon the consummation of the Transfer, Transferee shall
assume and shall be bound by and perform all provisions of Section 8 of the
Stock Purchase Agreement as if a signatory thereto.

     3.  (a) The "3.5% Condition" is triggered by the Transfer; (b) Investor
Director, Robert J Lievense, shall immediately resign in anticipation of the
Transfer in accordance with Section 6 of the Stock Purchase Agreement; and (c)
all rights of the Transferor under Section 6 of the Stock Purchase Agreement
have terminated.  Attached hereto as Schedule "A" is the proposed form of
resignation of Mr. Lievense.

     4.  The Company has not consented, and the Company's consent to this
Agreement shall not be construed as consent, to the assignment to Transferee of
any or all of Transferor's rights, if
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any, under the Stock Purchase Agreement.

     5.  Transferor reserves its rights, if any, to transfer any and all rights
under the Stock Purchase Agreement (other than Section 6 thereof which has
terminated as indicated above) to Transferee, including but not limited to
Section 9 thereof, and nothing herein shall be construed as a waiver of such
rights; provided however, that such rights are subject to all rights and
remedies of the Company to object or oppose any such attempted transfer, and
nothing herein shall be construed as a waiver of such rights and remedies of
the Company.

     6.  By consenting to this Acknowledgement Agreement by its execution as
below indicated, the Company shall agree that (i) upon receipt of the stock
certificates representing the Investor Shares and executed stock powers, it
will issue stock certificates representing such shares in the name of the
Transferee and (ii) all notices under the Stock Purchase Agreement will also be
delivered to the Transferee (the address for delivery to be provided to the
Company in writing).

     7.  The Company is a direct, intended third-party beneficiary of this
Acknowledgement Agreement and, as such, shall have standing to enforce its
rights hereunder.




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     IN WITNESS WHEREOF, the parties hereto have caused this Assumption and
Acknowledgement Agreement to be duly executed by their respective authorized
officers as of the day and year first above written.




                                      THE DUN & BRADSTREET CORPORATION,   
                                      Transferor                          
                                                                          
                                                                          
                                      By:    /s/ EARL H. DOPPELT          
                                         -----------------------------------
                                                                          
                                      Name:  Earl H. Doppelt

                                      Title:  Senior Vice President and   
                                      General Counsel                     
                                                                          
                                      Date:  June 20, 1996                
                                           ---------------------------------
                                                                          

                                      ACNIELSEN CORPORATION, Transferee  
                                                                          
                                      By:  /s/ ELLENORE O'HANRAHAN        
                                         -----------------------------------

                                      Name:  Ellenore O'Hanrahan          
                                           ---------------------------------

                                      Title:  Vice President and Secretary
                                            --------------------------------

                                      Date:   June 20, 1996               
                                           ---------------------------------
                                      

Consented to:

MANUGISTICS GROUP, INC.

By:   /s/ WILLIAM M. GIBSON
   ----------------------------

Name:  William M. Gibson

Title:  President & CEO



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