Theodoros Montesantos was born in Athens. He studied violin at the Greek National Conservatory under Spiros Demarias and Stelios Kafantaris (diploma and first prize) and orchestra conducting under the South-African conductor David de Villiers at the Folkwang Hochschule Essen, Germany. He has conducted numerous symphony orchestras and has worked with highly praised cultural institutions in Greece. Since the age of 22, he works with the GNO as a leading violinist while for eleven years he worked on a permanent basis with the Athens State Orchestra (KOA). He has conducted, at the GNO, productions of the works: O Vaftistikos (The Godson), Il barbiere di Siviglia, while he has also worked as assistant conductor in the operas Otello, Don Carlo, Nabucco, Carmen, Cavalleria rusticana (2010/11), Norma (2009/10), etc.