Jamie Roberts is joining Bath for next season after three years with Harlequins.
The 94-cap Wales centre and British Lion began his career with Cardiff RFC before spells with Cardiff Blues and French outfit Racing Metro.
Roberts said: “I’m really excited to have signed for Bath Rugby – it’s a club with a great deal of ambition, which was crucial in making my decision to come here.
“There is no doubt that Bath can mix it with the best in both the (Aviva) Premiership and in Europe over the next few years, and I’m looking forward to being part of the journey.
Bath’s Director of Rugby, Todd Blackadder said: “Jamie needs no introduction – he is a player with vast experience with two Lions tours and close to 100 caps for his country under his belt.
“We are delighted to bring someone of his quality to the Club, and I know will make an instant impact when he comes in this summer.
“He’s hugely respected both on and off the field, and it’s those qualities which makes this a really significant signing for the Club. Not only that, but he’s hugely ambitious and I believe that both Bath and Wales will reap the rewards from this move.”
Harlequins said they were unable to offer Roberts a contract having already signed Bath and Australia centre Ben Tapuai.
Director of Rugby John Kingston commented: “Jamie has been a model professional throughout his time at the Club. After much thought and reflection, it was decided that we would not be able to offer him a contract extension at the end of the season.
“His experience, focus and determination will be missed, but I have no doubt whatsoever that he will remain fully committed to the Club until the end of the season. On behalf of everyone at Harlequins I wish him well for the future and with the next chapter of his career.”