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 /70