The 31-year-old tighthead prop is the longest serving player in the Wasps squad and he moves after 13 years of service with the London club. Will has started on16 occasions for the reigning Heineken Cup champions this season and has a full set of England honours at U18, U21, Eng A and full level having toured South Africa a few seasons ago.
Will has represented Wasps in top class rugby since 1995. During that time he has collected four senior England caps, two domestic Cup winners' medals, three Premiership titles and a Heineken Cup winner's medal, including last year's Zurich Premiership and Heineken Cup double.
Speaking on Thursday, he said: "I'm very excited about joining such a top class outfit as Leinster. They are a top European side with many great players - six selected for the Lions says it all. I'm looking forward to experiencing a different way of doing things at one of the big Irish province teams and I hope I can get over there, get my head down and work hard and win silverware.
I've signed a two year deal with the club which gives Charlotte, me and our young son Arthur a change of lifestyle. Having lived in London for 9 years, we're ready for a change. I'm ready on the professional front for a new challenge, and on a private front my family and I are going to have an adventure, enjoying a different culture."
Leinster Chief Executive Mick Dawson added: "Leinster Rugby are delighted to welcome Will and his family to Ireland. Will is a top quality English forward and he has played an integral part in Wasps' recent success. I am confident that he will give added value to our squad for the seasons to come."
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