Regina Resnik (August 30, 1922 – August 8, 2013) was an American opera singer who had an active international career that spanned five decades. She began her career as a soprano in 1942 and soon after began a lengthy and fruitful relationship with the Metropolitan Opera that spanned from 1944 until 1983. Under the advice of conductor Clemens Krauss, she began retraining her voice in the mezzo-soprano repertoire in 1953 and by 1956 had completely removed soprano literature from her performance repertoire. 　　While the Met was Resnik's artistic home, she worked regularly as a guest artist with other major American opera companies and with the top European opera houses, including La Scala, the Paris Opera, the Royal Opera, London, the San Francisco Opera, and the Vienna State Opera. After the mid 1980s her performance career transitioned away from opera towards musical theater. 　　In addition to performing, Resnik worked as a stage director at several European opera houses during the 1970s and 1980s; usually in collaboration with her husband, scenic and costume designer Arbit Blatas. She was also highly active as a voice teacher, teaching on the voice faculties of several music conservatories, including the Juilliard School.