• 1966 – Qualified as a Swiss Air Force pilot
• 1974 – Qualified as an airline pilot (flying DC-9s for Swissair from 1974 to 1976)
• 1975 – Master of Science in astrophysics from the University of Geneva
• 1977-2007 – Selected as ESA European Payload Specialist for the first Spacelab mission, ESA Astronaut on four missions from 1992-1999 and was Lead ESA Astronaut in Houston
• 1988 – Graduated as test pilot at the Empire Test Pilots’ School, UK
• 2007 – Professor of Spatial Technology at the Swiss Federal Institute of Technology in Lausanne (Ecole Polytechnique Fédérale de Lausanne)

In 1977 Nicollier was selected as one of four European Payload Specialist Candidates for the first Spacelab mission, in ESA’s first astronaut selection. He joined Group 9 of NASA astronauts in 1980 for Space Shuttle training at the Johnson Space Center, Houston, Texas, where he was stationed until September 2005. Nicollier was a crew member on four Space Shuttle flights: STS-46 in 1992, STS-61 in 1993, STS-75 in 1996 and STS-103 in 1999. During his final spaceflight he became the first ESA astronaut to participate in a spacewalk during a Space Shuttle mission. In addition, from 1996 to 1998, he was Head of the Astronaut Office Robotics Branch, and from 2000, he was assigned to the Astronaut Office Extravehicular Activity Branch, while maintaining a position as Lead ESA astronaut in Houston. He retired from ESA in 2007.