London Welsh have signed flanker Darren Waters from Newport Gwent Dragons for the 2014-15 Premiership season.
He began his career at Pontypridd, scoring 11 tries in two seasons before moving to Newport in 2011.
However, the 29-year-old back row made only 17 appearances over three seasons for the Dragons.
"I've known Darren for a long time, and he's a sheer raw talent," head coach Justin Burnell told the London Welsh website.
"He's phenomenal at the breakdown, one of the best I've seen. He's going to be an absolutely fantastic asset and a really positive addition to our environment."
Waters is the club's 18th signing during the off-season, but they have also released 25 players, including New-Zealand scrum-half Tyson Keats.