Jones captains the team, as he does for the Ospreys, and the league leaders also contribute the half-back pairing in Biggar and scrum-half Rhys Webb, who has scored 17 tries for club and country this season.
Scarlets full-back Williams has continued his impressive form for his region and he is joined in the back three by Ulster’s Craig Gilroy – the league’s top try scorer this season – and Glasgow Warriors star Tommy Seymour.
The midfield sees young Connacht centre Robbie Henshaw paired with versatile Glasgow Warriors back Peter Horne, who has enjoyed a superb season for the club, whether playing at inside centre or stand-off.
Up front, Connacht’s Denis Buckley is named at loosehead prop with Edinburgh’s WP Nel capping off a fantastic season to take the tighthead berth, while Ulster centurion Rory Best is selected at hooker.
Partnering Jones in the second row is Ulster’s Franco van der Merwe, who joined the Irish province last summer from the Lions franchise in South Africa.
The back row sees Munster flankers CJ Stander and Tommy O’Donnell recognised for superb seasons with Glasgow Warriors’ Josh Strauss selected at number eight taking the number of South Africans in the team to four.
The Dream Team was voted on by a media panel of 11 journalists from all four countries that make up the PRO12 with only players who have made 10 appearances in the league this season eligible for selection.
Guinness PRO12 2014/15 Dream Team: Liam Williams (Scarlets); Tommy Seymour (Glasgow Warriors), Robbie Henshaw (Connacht), Peter Horne (Glasgow Warriors), Craig Gilroy (Ulster); Dan Biggar (Ospreys), Rhys Webb (Ospreys); Denis Buckley (Connacht), Rory Best (Ulster), WP Nel (Edinburgh), Alun Wyn Jones (Ospreys, captain), Franco van der Merwe (Ulster), CJ Stander (Munster), Tommy O’Donnell (Munster), Josh Stauss (Glasgow Warriors).
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