Ireland great Ronan O'Gara has been appointed head coach of French club La Rochelle.
O'Gara has been serving as backs coach with the Crusaders but will return to Europe at the end of the Super Rugby season.
He will succeed Xavier Garbajosa at La Rochelle, who finished fifth in the 2018-19 Top 14 campaign before being defeated by Toulouse in the semi-finals.
The 42-year-old O'Gara will move into his highest-profile role since turning to coaching.
He said: "My family and I have thoroughly enjoyed our time in Christchurch and were welcomed in to the Crusaders family with open arms when we arrived in early 2018. This is one of the best rugby clubs in the world, and it certainly wasn't an easy decision to move on from this team and their high-performance environment.
"I'm grateful to the Crusaders for the faith they've shown in me as a coach, and I'm incredibly fortunate to have worked alongside a world-class playing and management group for the last two seasons. While I see this move to La Rochelle as the next step in my coaching career and an exciting opportunity for my young family, I'd like to think, long-term, this is not necessarily the end of my time with the Crusaders.
"My focus now is helping to deliver a successful 2019 campaign with the side before my family and I return to France at the end of the season."
La Rochelle confirmed the appointment at a news conference, with director of rugby Jono Gibbes welcoming O'Gara.
"He knows the Top 14 well, he has the experience," Gibbes said.
Former fly-half O'Gara spent four years on the Racing 92 coaching staff before joining the Crusaders and helping the team land the 2018 Super Rugby title.
Crusaders head coach Scott Robertson said: "We've seen a huge amount of personal growth in Ronan during his time here, he continues to be a great friend to me and he's been an integral part of our success to date.
"On behalf of the Crusaders team, we wish Ronan and his family all the very best on their return to France."
O'Gara won 128 caps with Ireland, scoring a record number of points for his country, and was also a member of three touring British and Irish Lions squads.