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.