Professor Clements was the Foundation Director of the New Zealand National Centre for Peace and Conflict Studies (NCPACS) at the University of Otago, before retiring in 2020. He was the Secretary General of the International Peace Research Association and past Secretary General of The Asia Pacific Peace Research Association.
Prior to taking up these positions he was the Professor of Peace and Conflict Studies and Foundation Director of the Australian Centre for Peace and Conflict Studies at the University of Queensland, Brisbane, Australia.
His career has been a combination of academic analysis and practice in the areas of peacebuilding and conflict transformation. Professor Clements has been a regular consultant to a variety of non-governmental and intergovernmental organisations.
Today, he is Director of the Toda Peace Institute, in Tokyo, Japan.