Laidlaw heads to Clermont
The 31-year-old scrumhalf has won 53 caps for his country and is currently in his third season in the Cherry and White of Gloucester.
His current contract with Gloucester expires at the end of the 2016/17 season.
"I've thoroughly enjoyed my time at Gloucester. It's a fantastic club which enjoys tremendous support. The squad contains a great group of boys, I love playing at Kingsholm and it's been a genuine honour to captain the side.
"Since I first moved south, I feel that my game has developed tremendously for playing in the Gloucester team in the Premiership and it's a period of my career that I'll always look back on fondly.
"However, at this stage of my career, the offer to test myself and develop my game even further in a different environment was just too good to turn down. It's not been an easy decision to make, but I think it's the right one.
"There's so much I'll miss about Gloucester as a club and a place. However, there are still plenty of games left this season and a lot to play for, and I can guarantee that I will be giving 100 percent commitment to the Gloucester cause to help us achieve as much as possible in my remaining time here," Laidlaw said.
Director of Rugby David Humphreys paid tribute to Laidlaw and his contribution to the cause during his time in Cherry and White.
"Since all the changes at Gloucester ahead of the 2014/15 season, his consistent performances at both club and international level, particularly his goal-kicking, have caught the attention of some of the biggest clubs in Europe.
"While we are sorry to see him go, the offer Greig received from France was too good to turn down and, at the end of the season, we will wish him all the best for the rest of his career. For now, however, Greig will want to play a key role in helping us to turn our Premiership season around and help Gloucester finish the year on a high," Humphreys said.
