Ib Petersen has served as ambassador, and permanent representative of Denmark to the United Nations since August 2013. Before taking on that position, Ambassador Petersen served for four years as state secretary for development policy of the Danish Ministry of Foreign Affairs. Prior to that, he was state secretary for development cooperation, Middle East, Africa, Asia, Latin America and the United Nations.
Ib Petersen has held a variety of senior management positions in the Ministry of Foreign Affairs, including under secretary for bilateral development cooperation (2004–2007), head of department, policy and planning (2001–2004) and deputy head of department, development policy and planning (1998-2001).
From 1995 to 1998, he served as deputy head of the Danish Embassy in Zimbabwe and from 1988 to 1991 as adviser to the Nordic executive director on the board of the World Bank in Washington, D.C. He joined the Danish Foreign Service in 1985.
He has also served on the boards of Danish International Investment Funds: The Industrialization Funds for Developing Countries and The Investment Fund for Central and Eastern Europe and The Investment Fund for Emerging Markets.