Former England international Gareth Barry has joined Albion on an initial one-year contract.
It's believed Albion have paid Everton around £800,000 for the 36-year-old.
Barry is only four games away from breaking the record number of Premier League appearances after spells at Aston Villa, Manchester City and Everton.
Tony Pulis is delighted to sign somebody of Barry's experience after losing Darren Fletcher to Stoke City in the summer.
“There was a big void when we lost ‘Fletch’ and Gareth will fill that void,” said the head coach.
“He’s a fantastic player and I think his attitude towards playing is really gauged by the fact that Everton had offered him a two-year contract to stay there.
“He really wants to play and I’m really looking forward to working with him."
Despite his age, Barry made 34 appearances for Everton last season, scoring twice - including at The Hawthorns.
He becomes Albion's fourth signing of the summer after Jay Rodriguez, Ahmed Hegazi and Chinese youngster Yuning Zhang.
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