 Frey has also been Music Director for major productions at the Edinburgh International Festival (where he was awarded the festival's Critics' Prize), the Wiener Festwochen (Theater an der Wien, Vienna), Venice Festival (Teatro La Fenice), Holland Festival, the Fifth European Festival, the Copenhagen Opera Festival, Karlin Theater (Prague), Varna State Opera, Opera Română Craiova and the International Festival Elena Teodorini.From 1992 to 1996, he was Music Director of Germany's most renowned theater, the Berliner Ensemble, founded by Bertolt Brecht, where he collaborated with the celebrated stage director Peter Zadek.Frey was the first American to hold a position at the Berliner Ensemble, as well as being the theater's first non-German Music Director; his historic predecessors who held the same music directorship included the composers Kurt Weill, Hanns Eisler, and Paul Dessau.