London Welsh have confirmed four signings in James Sandford, Cameron Goodhue, Paul Rowley and Jesse Liston.
The announcement sees the number of new signings announced by London Welsh so far this week reach 14 as the Exiles make their Aviva Premiership return.
"Another four fantastic and exciting signings by the club for next season; Cameron has Super 15s experience, Jesse has just returned from England Counties duty in Georgia, Paul impressed against us last season for Plymouth Albion in the Championship and James is also very experienced and has a tremendous attitude - I very impressed when meeting him," said London Welsh head coach Justin Burnell.
Sandford, 25, joins Welsh from Cornish Pirates having previously played for London Irish, Ulster and Rotherham Titans.
A former Irish Schools captain, Sandford came through the Ulster Academy and represented Ulster at Under 20s and 18s, captaining them at the former grade.
Selected for Ireland at Under 20s and 18s, Sanford competed in two Six Nations championships and two World Cups with Ireland Under 20s. In 2009 he was named Ireland's Young Player of the Year.
After playing for Ulster 'A', he moved to Rotherham Titans under Andre Bester before leaving for London Irish, where he spent two years before joining the Cornish Pirates in 2013.
New Zealand-born back row forward Goodhue, 27, makes the switch to London Welsh from Worcester Warriors after one season at Sixways.
He featured in the J.P. Morgan Asset Management Premiership Rugby 7s Series before making his full senior debut for the Warriors against Newcastle Falcons in the Premiership.
Goodhue was previously part of the Auckland Blues set-up, making his Blues debut in Christchurch in 2012 against the Crusaders, and also featured for Northland.
Rowley, 26, played a starring role in Plymouth's Albion 36-15 victory over Welsh at Brickfields in February.
The scrum-half joined Albion in 2011 from Munster where he came through the Academy. In his five years at Munster, Rowley gained experience in the Pro 12, British & Irish Cup and with Munster A.
From Limerick, Rowley played his schools rugby with St. Munchins and represented Ireland and Munster Schools. He also played for Munster at Under 19 and 20.
He played his club rugby in Ireland for UL Bohemians and Shannon RFC.
Rowley qualified as an EQP player in June after three years playing in England.
Back row forward Liston, 20, joins London Welsh from National League One side Blackheath, for whom he made 27 appearances in National League One last season, scoring four tries.
He was last month named in the England Counties 26-strong squad for the two-match tour of Georgia in June, having been part of the England Counties Under 20s trip to Georgia in 2013.
Liston has also represented Kent in the County Championship and on June 1 helped the county to victory over Durham at Twickenham in the County Championship Plate Final.
He has also played for London & South East and Canterbury RFC.