Mildred Miller Posvar (1924–2023) was a celebrated American mezzo-soprano who captivated audiences with her powerful voice and emotive performances. Born in Cleveland, Ohio, Miller's illustrious career spanned over two decades at the prestigious Metropolitan Opera, where she sang in 338 performances. Her repertoire included a wide range of operatic roles, showcasing her versatility and artistry. Beyond her stage presence, Miller was also a dedicated mentor and coach, founding the Opera Theater of Pittsburgh in 1978, which continues to thrive as the Pittsburgh Festival Opera. Her legacy as a recording artist and educator cemented her status as a cherished figure in the world of classical music.