Australian diplomat and expert involved in the 1995 Non-Proliferation Treaty Extension Conference.

Member of South Africa’s delegation to the 1995 NPT review conference.

Chairperson of the subcommittee for "Disarmament, Arms Control, and Nonproliferation" of the Foreign Affairs Committee of the German Bundestag.

Permanent Representative of Venezuela to the United Nations (1993-2017)

Deputy head of the nuclear non-proliferation section of the economic department in the German Federal Foreign Office.

Co-founder of the Programme for Promoting Nuclear Non-Proliferation (PPNN) and advisor to the Conference President Dhanapala.

Ambassador and Permanent Representative of the Kingdom of the Netherlands to the Conference on Disarmament in Geneva.

Senior Advisor for Non-proliferation and Deputy Director of the Non-proliferation, Arms Control and Disarmament Division of the Canadian Department of Foreign Affairs.

Untied States special representative for Arms Control, Non-Proliferation, and Disarmament.