St. Hallvard-guttene is a Norwegian boys choir founded by former conductor Øystein Vogt. The choir is named after Oslo's patron saint, Saint Hallvard. The choir sings in their characteristic burgundy monk's robes. The choir has a large repertoire which includes church music, medieval music, renaissance music, folk music and modern music. The choir is well known for being specialized in Gregorian music. The current conductor is Hans Dur Molvik, who has been conducting since 2007.