Leinster have confirmed that Stuart Lancaster will join Racing 92 at the end of the season.
Lancaster, who joined Leinster as a senior coach in 2016, has signed a four-year deal to become director of rugby at the Pro 14 club.
The 52-year-old will replace current Racing head coach Laurent Travers, who will move into a new role as chairman of the club's management board.
Leinster have enjoyed a period of sustained success since the former England head coach's arrival, winning the Heineken Champions Cup and four PRO14 titles during Lancaster's time working under head coach Leo Cullen at the province.
“I will be eternally grateful to Leo, Mick and Guy and the whole Leinster organisation for the opportunity they gave me and my family back in 2016," Lancaster told the province's official website.
“Initially it was for just one season and here I am entering my seventh and that is a reflection on all the players past and present I have worked with and the people of Leinster and Ireland who have made me and my family feel so welcome.
“I have always wanted to challenge myself as a coach in different ways and the opportunity to coach in France at a club like Racing 92 is an exciting one and I will look forward to that challenge when it comes.
“In the meantime, I really want to give everything to the whole of Leinster Rugby and the supporters in the next eight months as I feel we have more to come as we drive towards the exciting challenge ahead both in the URC and in Europe.”