Andy Farrell is to rejoin the England coaching team on July 2, the Rugby Football Union have announced.
Farrell has signed a contract through to January 2016 and he will take charge of England's backs and defence for their tilt at World Cup glory on home soil in 2015. The former dual international was part of Stuart Lancaster's interim coaching team for this year's RBS 6 Nations, which guided England to second place in the championship.
Farrell initially decided his coaching future lay with Saracens, who had released him on secondment to England, but changed his mind at the end of the Aviva Premiership season.
"I loved every minute of coaching England and working with Stuart and Graham Rowntree and this group of players in the Six Nations and to get the opportunity to do it permanently is a dream," said Farrell.
"I have watched England in South Africa and I am massively excited about the potential that was clearly evident in the three Tests and midweek matches.
"I had seven very special years with Saracens and the club will always have a fond place in my heart. I am grateful for the help they have given me as a player and a coach and I wish everyone involved the best in the future."
Farrell was replaced for England's summer tour of South Africa by Mike Catt, who is still under consideration for a role in an expanded four-man senior coaching team.
"I will continue to review the make-up of the coaching team over the next few weeks to ensure that England has the best structure and personnel," Lancaster said.
"I am delighted that we have got Andy on board. He is a special coach and an individual and the way this team has developed is a testament to the foundations that we laid in the Six Nations.
"Andy, Graham and myself work well together and I am looking forward to carrying on that close relationship over the next three-and-a-half years as we build towards a home World Cup."