POWER OF ATTORNEY

    The undersigned hereby appoints Michael W. Conron,
Sean E. Dempsey, Mark A. Shelnitz and Thomas E. Blaser as
his true and lawful attorneys-in-fact for the purpose of
signing Statements on Forms 3, 4 and 5, and all amendments
thereto, to be filed with the Securities and Exchange
Commission with respect to the holdings, and future
changes in such holdings, for the undersigned in securities
of W. R. Grace & Co., for the term of his employment with
W. R. Grace & Co.  Each of such attorneys-in-fact is
appointed with full power to act without the other.


                /s/ Shlomo Yanai
                (signature)



                Shlomo Yanai
                (printed name)





Dated:     May 9, 2018