Jorg Zander will return to Sauber, taking up the role of technical director at the Formula One team.
Zander comes with F1 pedigree having previously worked for BAR Honda, Williams and Brawn GP, and spent a two-year spell as chief designer for Sauber from 2006.
The 52-year-old German has opted to leave his role as technical director for Audi Sport in order to return to the Swiss team.
"I am delighted to return to the Sauber F1 Team in my adopted home country of Switzerland," Zander said in an official Sauber statement.
"After many years at the top level in endurance motorsport, I am very pleased to become technical director and to undertake the challenge with [chief executive and team principal] Monisha Kaltenborn, the team, all the outstanding engineers and mechanics in the new era of Formula 1.
"The new Formula 1 regulations offer a great opportunity to point the way with innovations and technical creativity.
"One of my tasks will be to define a stable and efficient technical organisation that evolves the potential of creativity and, therefore, the basis for the development of successful Formula 1 cars.
"Initially we obviously want to improve and establish ourselves as a team in the mid-field. Overall it is a challenge which I await with excitement and enthusiasm."