[1] Collomb was a member of the Institut de France (Académie des sciences morales et politiques).

Collomb was a director of several international companies, including Allianz, Unilever, Vivendi, DuPont, Total and ATCO.

He was also the chairman of the World Business Council for Sustainable Development in 2004–2005, and of the think tank Institut français des relations internationales.

Collomb was part of the "Coppens commission" which prepared the French Charter for the Environment of 2004.

Collomb graduated in 1960 from the École Polytechnique and the Ecole des Mines with a degree in law.