He worked for seven years for Jaeger-LeCoultre and contributed significantly to the strong revenue growth of this manufacturer. In 1998, when he was only 31 years old, he became managing director at Harry Winston in Geneva. Again he is credited for strong growth there during his seven year tenure, including launching and managing the influential Harry Winston Opus program.
In July 2005, at the age of 38, Büsser launched his own brand, MB & F (Maximilian Büsser & Friends). The company targets revolutionary new approaches in the field of Haute Horlogerie and ventures into uncharted territory of design. With its unusual and provocative creations such as Horological Machine no. 1 (HM1), HM2 and HM3, he caused a great sensation in the field.