Hans-Peter Gasser was born in Zurich, Switzerland in 1939. He is a Swiss national, married and has two sons, who are at university. After attending primary and secondary schools in Zurich, Mr Gasser read law at the University of Zurich and received a doctorate in 1965. He also holds a Master of Law (LL.M.) degree from Harvard Law School (United States).

Mr Gasser began his professional life as a clerk at the Winterthur District Court in the Canton of Zurich. He then worked as a lawyer in the Swiss Federal Department of Public Economy and later as Deputy General Secretary of the Swiss Science Council. In 1970 he joined the ICRC and was posted as a delegate in the Middle East, where he acquired sound practical experience during two years' field work in Israel and the occupied territories. He was appointed Head of the ICRC's Legal Division in 1977 and remained in charge of it for almost five years. From 1983 to 1995 he was senior legal adviser to the ICRC and was attached to the staff of the Director of the Department for Principles, Law and Relations with the Movement. His duties in that capacity were many and varied he was above all responsible for promoting the ratification by States of the 1977 Protocols additional to the Geneva Conventions. This task enabled him to establish close and regular contact with many governments and National Red Cross or Red Crescent Societies throughout the world.

Mr. Gasser has written articles on various aspects of international humanitarian law, some of which have appeared in the International Review of the Red Cross. He has also written an introduction to international humanitarian law which has been published in several languages, and regularly gives lectures on international humanitarian law for academic audiences.