Ibrahim Thiaw is Under-Secretary-General and Executive Secretary of the United Nations Convention to Combat Desertification (UNCCD) since February 2019.

Mr. Thiaw brings to the position 40 years of experience in sustainable development, environmental governance and natural resource management. In 2018, he was Special Adviser to the Secretary-General for the Sahel and supported ongoing efforts to advance the recalibration of the United Nations Integrated Strategy for the Sahel (UNISS) and the development of the UN Support Plan for the Sahel.

Prior to this position, from 2013 to 2018, he served as Assistant Secretary-General and Deputy Executive Director of the United Nations Environment Programme (UNEP), where he played a key role in shaping the organization's strategic vision and mandate, overseeing the development and implementation of the mid-term strategy and programme of work, and strengthening collaborations with Governments and other environmental governing bodies. Mr. Thiaw joined the United Nations in 2007 as Director of UNEP’s Division for Environmental Policy Implementation.

Before joining the Organization, he was the Regional Director for West Africa, and later Acting Director General, of the International Union for Conservation of Nature (IUCN).

Mr. Thiaw started his career in Mauritania, his home country, where he served in the Ministry of Rural Development for 10 years. He holds an advanced degree in forestry and forest product techniques.