António Guterres has been at the helm of the United Nations High Commission for Refugees since June 2005.
Filippo Grandi (58), who used to be responsible for the Palestinian refugees, is to take over on 1 January 2016.
António Guterres is to leave the post at the end of the year after leading the UN efforts to help 60 million people all over the world who have been forced to leave their homes and countries because of wars and persecution.