Lyon have completed the signing of right-back Christophe Jallet from Ligue 1 champions Paris Saint-Germain.
The 30-year-old joins OL on a three-year deal after five years in the capital which saw him play an integral part in winning two Ligue 1 titles, the Coupe de France and the Coupe de la Ligue.
"This is an important moment for the club because, first of all, he is a really good guy so it's a very positive relationship," Lyon president Jean-Michel Aulas said in a statement on the club's website.
"Above and beyond that, he is a player that will bring to OL exactly what the club was lacking.
"He's a right-back with a lot of experience who arrives here from the French champions. It's exactly the profile of player we were looking for. He was our first and last choice."
Jallet made his professional debut for Niort before spending three seasons with Lorient and eventually moving to PSG in 2009.
While at the Parc des Princes, Jallet earned five France caps but has decided to move on, with the emergence of Gregory van der Wiel and PSG's signing of Toulouse full-back Serge Aurier likely to impact further on his first-team chances.
"OL has had an ambitious project for a number of years," he said. "It's a project that suits me, both on a sporting and human level.
"As soon as Lyon expressed an interest in signing me, they were my priority. I am very happy to be here today. This is a new challenge for me.
"I had an interesting career and now I want to keep progressing.
"I spent some great moments in Paris, but I needed to transfer somewhere else to see more playing time and enjoyment. That was also a factor in my choice.
"I am delighted to be joining this quality squad to try and do my bit to ensure we have a great season."