Kidney, who led Ireland to a Grand Slam in 2009, has been appointed as the Premiership club’s technical consultant with Kiss named head coach.
The pair have both signed three-year deals and will work alongside director of rugby Nick Kennedy.
Kiss and Kidney worked together between 2008 and 2013 with Ireland. Since then Kidney was Director of Sport and Physical Activity at UCC while Kiss continued to work with the national side before being appointed Ulster’s director of rugby — leaving Ravenhill in January.
London Irish are 12 points adrift at the bottom of the Premiership with five games left, having won just two of their 17 matches this season.
“London Irish is a club with a proud and rich tradition, both in London and in Ireland, and I had no hesitation in agreeing to join the team at Hazelwood,” said Kidney.
“It is a club which has a history of producing quality young players, and there appears to be a group of coaches with plenty of promise, and an off-field management team which is putting everything in place for a bright future. I’m under no illusions that this is going to be a challenging job.
“English club rugby is very competitive, and it is going to take several years for us to cement a place at the top end of the Aviva Premiership, but I believe that with the right structures this becomes a realistic ambition for us.
“I’m particularly excited to be working with Les Kiss again”.
Kiss added: “Declan is a great person to work with, and I’m looking forward to joining him at London Irish,” he said.
“It is a big job for us, but one we are relishing. There are some good coaches already at Hazelwood, the likes of Nick Kennedy, Declan Danaher, Paul Hodgson and George Skivington, who have all shown their commitment to the club for several years, and we believe that we will be able to help them reach their potential.”
London Irish chief executive Brian Facer says that the appointments mark the start of a new era.
“Declan and Les have a great working relationship and huge experience of what it takes to be successful in elite rugby.
“They will be invaluable in helping London Irish re-establish itself as a force in the Aviva Premiership.”