Dean Richards has been confirmed as director of rugby at relegated Harlequins on a three-year contract.
Richards won four league titles at Leicester
The former Leicester boss, who spent this season at Grenoble, vowed to get Quins straight back to the top flight.
"I'm really looking forward to taking them back to the Premiership in 12 months time," said Richards.
"Having played against Quins for 20 years and having been director of rugby against them, I always felt they are sleeping giants waiting to be woken."
Quins also announced sponsors NEC had signed a new two-year deal allowing them to re-sign key players.
Club captain Andre Vos, England centre Will Greenwood and number eight Tony Diprose will all remain at The Stoop.
The 41-year-old Richards said there was "huge potential" at the Stoop. "And I am here to realise that potential. I am looking to do something here at Quins. Without a doubt I think people will expect success.
"My first objective is to get into the Premiership but it's going to be a hard year. The situation most of the players find themselves in will be alien."
Club chief executive Mark Evans said he was sure Richards could return Quins to the top.
"I'm extremely confident he will not only lead us out of Division One at the first attempt but also make us a formidable force on our return to the Premiership," said Evans.
"Perhaps even more important, his personal qualities and commitment to vital components, such as honesty and integrity, made him the outstanding candidate amongst the huge list of interested candidates."
Richards spent this season at Grenoble after being forced to quit Welford Road following a dip in the Midlands club's results.
During his time as Leicester coach, Richards led the club to four consecutive league titles in England (1998/99 to 2001/02) as well to back-to-back victories in the Heineken Cup (2000/01 and 2001/02).
As a player, Richards won 48 England caps and six Lions caps between 1982 and 1997, as well as making 314 appearances for Leicester.
In addition to Richards joining Quins, assistant coach John Kingston has signed a new two-year contract, having joined the club in the summer of 2001 from Irish club side Galwegians.