Staffan de Mistura is a veteran Italian-Swedish diplomat who has had a 40-year career with the United Nations, including a number of high-profile roles. Latterly he also served as Italy's deputy foreign minister.
In July 2014 he was chosen by UN Secretary General Ban Ki-moon to replace Lakhdar Brahimi as the international mediator seeking an end to Syria's civil war.
Mr de Mistura's previous UN roles have included UN envoy in Afghanistan in 2010-11, and in Iraq in 2007-09. He was also the UN secretary general's personal representative to southern Lebanon in 2001-04.
His predecessor as the UN's top envoy to Syria was veteran Algerian diplomat Lakhdar Brahimi, who resigned in May after the failure of the second round of Geneva talks in January and February.
Mr Brahimi had spent two years in the position, which he assumed after former UN chief Kofi Annan stepped down following six months in the role.
Speaking on Mr de Mistura's appointment, Ban Ki-Moon said the new special envoy would "bring all his expertise and experiences to this very difficult negotiations for peace in Syria." In his Syria role, Mr De Mistura serves only as a UN envoy, not the joint UN-Arab League envoy, as Mr Brahimi was.
Staffan de Mistura began his UN career in 1971 as a World Food Programme project officer in Sudan. Over the years his work has taken him to many of the world's trouble spots including Somalia, Ethiopia, the Balkans and Rwanda.
He has also served as Director of the UN Information Centre in Rome, Director of Fundraising and External Relations of the UN Office of the Co-ordinator for Afghanistan (1989-1991), and has held a variety of senior posts with Unicef, the UN agency for the care of children worldwide.
Mr de Mistura is 67 and speaks seven languages including colloquial Arabic, according to the Italian Foreign Ministry website.
While working as a deputy foreign minister in Mario Monti's technocratic government, he was sent to India in 2013 to lead Italian negotiations with the Indian government over the arrest of two Italian marines over the shooting dead of two Indian fishermen mistaken for pirates.
Mr de Mistura was born in Stockholm in 1947 of a Swedish mother and an Italian father, and has dual citizenship. He is a graduate of the University of Rome with a degree in Political Science and Development Economics. He is married with two daughters.