Exhibit 10.15


    
      

    

     

    Exhibit
      10.15

      STRATEGIC
        ALLIANCE NETWORK

      


      18101
        Von
        Karman Avenue

      Suite
        330

      Irvine,
        CA 92612

       

      


      May
        16,
        2007

      


      


      Windy
        City, Inc.

      8000
        Towers Crescent Drive, Suite 1300

      Vienna,
        Virginia 22182

      


      
        	 	 	
                Re:

              	
                Consulting
                  Agreement

              


      

      


      Gentlemen:

      


      The
        undersigned hereby agree that, pursuant to the terms and conditions set forth
        in
        this letter agreement, Strategic Alliance Network, LLC (“SAN”) shall perform for
        Windy City, Inc. (“Windy
        City”) consulting
        services, which shall include but not be limited to, the review and analysis
        of
        the financial statements of XLNT Veterinary Care, Inc. (“XLNT”) and its
        subsidiaries, the monitoring and evaluation of XLNT’s compliance with its
        agreements with Echo Healthcare Acquisition Corp. (“Echo”) and the assistance
        with the preparation of financial statements and reports for Echo (“Consulting
        Services”), in connection with the merger (“Merger”) by and among Echo,
Pet
        DRx Acquisition Company, a newly formed, wholly-owned subsidiary of Echo,
        and
        XLNT. In
        consideration of the Consulting Services, Windy
        City shall pay SAN
        a
        fee of $10,000 per month, plus all reasonable, documented out-of-pocket expenses
        incurred by SAN in connection with this engagement, commencing on April 1,
        2007
        and continuing monthly thereafter until the Termination Date. SAN agrees
        to
        defer $3,000 per month of such fee until the Termination Date. For purposes
        of
        this letter agreement the “Termination Date” shall be the earlier of the closing
        date of the Merger or the date on which the Merger is terminated. All deferred
        fees shall be due and payable on the Termination Date unless otherwise agreed
        to
        by SAN and Windy City.

      


      Each
        of
        the undersigned has full right and power, without violating any agreement
        by
        which the undersigned is bound, to enter into this letter
        agreement.


      
        
           

        

        
           

          
            

          

        

        
           

        

      


      


      This
        letter agreement shall be governed by and construed and enforced in accordance
        with the laws of the State of Delaware, without giving effect to conflicts
        of
        law principles that would result in the application of the substantive laws
        of
        another jurisdiction.   

      


      


      


      STRATEGIC
        ALLIANCE NETWORK, LLC

      


      


       
        /s/ Kevin
        Pendergest                              


      Kevin
        W.
        Pendergest

      


      


      


      WINDY
        CITY, INC.

      


      


       /s/
        Joel
        Kanter                                          


      Joel
        Kanter