Nico Rosberg has signed a "multi-year contract extension" with Mercedes, the team have announced.
The German is currently midway through his fifth and best season with the team, leading the way in the race for the World Championship.
He heads team-mate Lewis Hamilton by four points going into this weekend's German Grand Prix and ahead of that, the 29-year-old is pleased to have signed the new deal.
"I am very proud to drive for the Formula One Silver Arrow of the modern era," he told Mercedes' official website.
"As a German, the heritage of Mercedes-Benz is very special for me, and I am proud to be able to represent the best car brand around the world.
"It has been a difficult road to get to where we are now but everybody kept believing and, thanks to the fantastic support from Mercedes-Benz, we are now leading the way in F1."
Rosberg leads the way from Hamilton too, with his 165 points shading the Briton's 161 despite Hamilton winning five grands prix to his three.
A fierce rivalry has developed between the two old friends - to the point of spilling over into conflict at times - but Rosberg is pleased to see the team progressing.
"There has been big progress during the past year, building up our structure, management and capability for the future," he said.
"We have an awesome team and I am confident that we have the right people in place at every level. I'm looking forward to the next years together, when we will keep pushing to win even more races and, hopefully, championships."
Rosberg has won six races and had 18 podium finishes since moving to Mercedes and Toto Wolff, the head of motosport for the team, is thrilled to have secured his man's services for the future.
"Nico has been part of the Silver Arrows project since day one and he has had a big stake in the development of the team since 2010," he said.
"His speed, commitment and focus have all helped to give clear direction and to drive the team forward. With his performances in 2014, Nico has demonstrated to the outside world what we knew already in the team; that he is one of the very top drivers in Formula One.
"This new contract brings us important stability and continuity for the future and I am delighted to be able to make the announcement in time for the home race of Mercedes-Benz and Nico in Hockenheim."