EXHIBIT 25

                          POWER OF ATTORNEY

    We, the undersigned officers and directors of Ionics, Incorporated (the
"Company"), hereby severally constitute Arthur L. Goldstein and Stephen
Korn, and each of them, to sign for us, and in our names in the capacities
indicated below, the Annual Report on Form 10-K of the Company for the
fiscal year ended December 31, 1994, and any and all amendments to such
Annual Report, hereby ratifying and confirming our signatures as they may be
signed by our attorneys to such Annual Report and any and all amendments
thereto.

    Witness our hands on the respective dates set forth below.

     Signature                      Title                    Date


/s/William L. Brown                 Director               March 29, 1995 
William L. Brown

/s/Arnaud de Vitry d'Avaucourt      Director               March 29, 1995 
Arnaud de Vitry
   d'Avaucourt

/s/Lawrence E. Fouraker             Director               March 29, 1995 
Lawrence E. Fouraker

/s/Samuel A. Goldblith              Director               March 29, 1995 
Samuel A. Goldblith

/s/Arthur L. Goldstein              Chairman of the Board  March 29, 1995 
Arthur L. Goldstein                 of Directors, Chief
                                    Executive Officer and  
                                    President (Principal
                                    Executive Officer)

/s/Kachig Kachadurian               Director               March 29, 1995 
Kachig Kachadurian

/s/William E. Katz                  Director               March 29, 1995 
William E. Katz

/s/Robert B. Luick                  Director               March 29, 1995 
Robert B. Luick

/s/John J. Shields                  Director               March 29, 1995 
John J. Shields

/s/Carl S. Sloane                   Director               March 29, 1995 
Carl S. Sloane

/s/Mark S. Wrighton                 Director               March 29, 1995 
Mark S. Wrighton

/s/Allen S. Wyett                   Director               March 29, 1995 
Allen S. Wyett

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