West Brom have completed the double signing of Arsenal left-back Kieran Gibbs for about £7m and Paris St-Germain midfielder Grzegorz Krychowiak on loan.
England international Gibbs, 27, has agreed a four-year deal.
Poland international Krychowiak has started just 10 games for the French club since joining from Sevilla for £28m last year.
They are the Baggies' fifth and sixth major signings of the summer.
Krychowiak won two Europa League titles with Sevilla and won the Trophee des Champions, Coupe de la Ligue and Coupe de France last season at PSG.
The midfielder, who has 45 caps for Poland, said: "I had a lot of offers from Spain and Italy. But this is a very ambitious club. There's a good atmosphere here."
Gibbs had also been in talks with Watford and Turkish side Galatasaray this summer, while Krychowiak had reportedly been interesting clubs including Chelsea and Juventus.
"They've made some good signings and I feel this is a good move for me," said Gibbs, who has been at Arsenal since the age of 14.
Gibbs has 10 England caps, the last coming in a 2-0 win over France in a friendly at Wembley in November 2015.
"We have recruited another quality addition; an England player with bags of experience at Premier League and Champions League level," said Albion chairman John Williams.
Since the end of last season West Brom have signed Southampton striker Jay Rodriguez, 28, for about £12m, Egypt defender Ahmed Hegazi, 27, on a season-long loan deal, and former England midfielder Gareth Barry, 36, for an undisclosed fee.
Scotland winger Oliver Burke joined last week from German club RB Leipzig on a five-year contract for a reported fee of £15m.
The Baggies have also signed China striker Yuning Zhang, 20, who has started a two-year loan in Germany with Werder Bremen.
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