In 1998 and just 31 years old, Büsser was headhunted from Jaeger-LeCoultre to become CEO of Harry Winston, Inc. Rare Timepieces based in Geneva.
In his seven years at Harry Winston Rare Timepieces Büsser (bought by The Swatch Group in 2013) increased revenue from $8 million to $80 million and created the ground-breaking Opus series of ultra-complicated mechanical watches in collaboration with independent watchmakers [REF].