Casei “in the 1960s and ’70s could be reliably heard as Suzuki, Maddalena, Lola and other bread-and-butter mezzo-soprano characters at the Metropolitan Opera before transforming herself into a pathbreaking labor leader.” She performed at the Met for 20 years, starting with Maddalena in Rigoletto and ending as Larina in Eugene Onegin. Then she became president of the American Guild of Musical Artists – and she was a transformational labor leader for the performers’ union. – The New York Times