The Social Democratic Union of Macedonia (Macedonian: Социјалдемократски сојуз на Македонија Socijaldemokratski sojuz na Makedonija SDSM) is a social-democratic political party in Macedonia.It is the successor of the League of Communists of Macedonia the ruling party during the communist regime which ruled SR Macedonia as a constituent republic of SFR Yugoslavia from 1945 to 1990. The current party leader is Zoran Zaev.