Volkswagen AG has made several leadership changes at Audi AG, including naming a new chairman and technical development director, Audi has announced.

Matthias Muller takes over as chairman of Audi's Supervisory Board, following his appointment as chairman of Volkswagen AG in the wake of the diesel emissions crisis. Muller is also a member of Volkswagen AG's Board of Management. Prior to that, Muller was chairman of the board for Porsche AG.

In a related move, Stefan Knirsch joins Audi's board overseeing technical development for the luxury brand. Knirsch starts in his new role on Jan. 1. Since May of 2013, he has served as head of powertrain for Audi.

Knirsch, 49, replaces Ulrich Hackenberg, who has left the company after a mutual agreement. Terms of the agreement we not disclosed. Hackenberg was a company veteran with 30 years of service. He had joined the board on July 1, 2013.