Pat Symonds has left Marussia to take up a new role as chief technical officer of Williams, commencing on August 19.
Meanwhile Williams has also confirmed that technical director Mike Coughlan has parted company with the team.
Symonds had spent two and half years with Marussia, in effect rehabilitating his reputation after the Crashgate scandal at Renault left him on the sidelines.
Williams was in dire need of a new technical chief, having missed out on the opportunity to take Paddy Lowe.
Sir Frank Williams said: “I’m delighted that Pat is joining the team. His technical capabilities and sporting successes speak for themselves and I’m sure that his knowledge and leadership will contribute considerably to the success that all of us at Williams are working hard to achieve.”
Pat Symonds said: “Williams is a team steeped in success and engineering excellence and I’m honored to be asked to play a role in returning the team to its rightful place at the pinnacle of Formula One. Sir Frank, Mike and Claire have put in place the foundations for success and I’m immensely excited to begin this new challenge.”
Regarding Coughlan Williams said he “…has stepped down from his position as Technical Director and will leave the team with immediate effect. The team thanks him for the significant contribution he has made since 2011 and wishes him well in his future endeavors.”
Earlier a statement from Marussia said: “The Marussia F1 Team and its Technical Consultant Pat Symonds have reached an agreement for Pat to relinquish his responsibilities to the Team with immediate effect,” adding “with Pat moving on to explore new opportunities, the Marussia F1 Team looks forward to announcing its own plans for the continued development of its growing technical operation in due course.”
John Booth said: “We have some very talented design and engineering groups in place who have achieved great things over the past few seasons and who are excited about maintaining our current positive trajectory, boosted of course by our new powertrain partnership with Scuderia Ferrari. We would like to thank Pat for the contribution he has made to the development of that structure. We look forward to announcing plans for our continued growth when it is appropriate to do so.”