Sir Dave Brailsford has stepped down as British Cycling performance director to concentrate full-time on his role as Team Sky principal, the national governing body has confirmed.
Brailsford has led Britain's cyclists to an unprecedented period of success, with eight gold medals at the Beijing and London Olympics and has arguably been more influential than any other person in turning cycling into a mainstream sport in this country.
The 50-year-old Welshman also established Team Sky, winning the Tour de France through Sir Bradley Wiggins in 2012 and Chris Froome in 2013.
"This is a big step but it is the right decision for the team and for me," Brailsford said.
"Since London 2012, we have worked hard on succession planning and that has meant we've got to a point where I can move on, knowing the team will go from strength to strength."
The decision was made following an internal review.
Shane Sutton, Brailsford's right-hand man in more than a decade of success and previously performance manager, has been named technical director, while Andy Harrison will continue as programmes director.
A new role of head of performance support will be created.
As well as Brailsford, Professor Steve Peters will leave British Cycling, stepping down as the team's psychiatrist.
Peters now works with a range of other individuals and teams and will work with England's footballers ahead of the World Cup in Brazil this summer.
Brailsford added: "I'll still be available to Ian, Shane and Andy for support if they need it and my role at Team Sky will mean we'll still work closely and support the aims of British Cycling.
"I'd like to thank all the great staff who I've worked with and of course the amazing athletes who ultimately deserve all the credit for their success.
"I have some extraordinary memories - not just from Olympic Games and World Championships, but also just day to day seeing cycling go from a fringe activity to a mainstream sport.
"I've always said that, more than any of the medals, the transformation of cycling in Britain is the single thing I'm most proud of having helped achieve."
The success of Team Sky has effectively forced Brailsford's hand as he has determined that the two jobs have become too big for one man to combine.
This is gearing up to be another big year for Team Sky with the Tour de France starting in Yorkshire and the Giro d'Italia in Belfast.
The team is also opening a new performance centre in the south of France which would have pulled Brailsford away from British Cycling's Manchester base.
Brailsford, who considered his future with British Cycling after the London Olympics before deciding to stay on, has missed two successive Track World Championships due to Team Sky commitments, including February's event in Cali, Colombia where a disappointing performance prompted a fresh review of team operations.
Brailsford joined British Cycling in 1998 and took over as performance director when Peter Keen left in 2003.
His focus on mental preparation and the exploitation of "marginal gains" revolutionised the culture of the sport and led to a glittering array of honours.
Brailsford was knighted after the London Games.
Brailsford and Peters played leading roles in the review and were confident the structures they put in place have left the organisation in a position to continue to go from strength to strength.
British Cycling chief executive Ian Drake said: "I want to thank Sir Dave Brailsford for his enormous contribution to British Cycling - the organisation he leaves behind is transformed from the one we both joined in 1998.
"In that time the Great Britain cycling team has not only set the standard by which British sporting success is judged but also inspired millions of people to get active through cycling.
"The sport of cycling in this country has travelled a long way in the last few years but the best is yet to come."
Peters was influential in the long and successful careers of Olympic champions including Sir Chris Hoy and Victoria Pendleton. He will help implement a new support system before he departs.
"It has been an amazing 10 or so years and I consider myself fortunate to have been part of a team which has achieved such great things," Peters said.
"However, I think the time is right for a change and I look forward to seeing the team prosper."
Sutton paid tribute to Brailsford, acknowledging his friend's contribution.
Sutton said: "He leaves a big hole but we have a fantastic system in place from playground to club to podium with a great team throughout the organisation and I am very confident looking ahead to Rio.
"Andy and I know we can always pick up the phone to Sir Dave but in the meantime we are looking forward to getting on with the business of winning medals and working with an exciting generation of talented British cyclists."