Mavroyiannis joined the
Ministry of Foreign Affairs' diplomatic service in 1987. Mavroyiannis was Cyprus'
ambassador to the
United Nations from 2003 to 2008, and 2019 to 2021. He was one of the vice presidents of the 62nd session of the
United Nations General Assembly. He also served as Cyprus' ambassador to the European Union from 2008 to 2011, Ireland, and France. During the
Cyprus peace process Mavroyiannis served as chief negotiator under President
Nicos Anastasiades from 2012 to 2022. He was the Deputy Minister for European Affairs from 2011 to 2013, and Permanent Secretary of the Ministry of Foreign Affairs in 2013. Mavroyiannis ran in the
2023 presidential election as an
independent candidate.
Nikos Christodoulides defeated him in the second round of voting. In 2023, Mavroyiannis was appointed to a five-year term on the
International Law Commission. He is an adjunct professor at
Frederick University. ==Personal life==