Leslie Glass was raised in New York City. She studied music at Mannes College and received a BA from Sarah Lawrence College where she studied under Joseph Campbell and Grace Paley.

An active philanthropist, Glass has been involved with a variety of non-profit organizations. She has served as the president of Plays for Living, as the vice president of the Asolo Repertory Theatre, as a public member of the Middle States Commission of Higher Education, and as a board member of the Mystery Writers of America and the Sarasota Reading Festival.

Additionally, in 1990 she established the Leslie Glass Foundation, which provides fellowships at NYU, the CUNY Graduate Center, the John Jay College of Criminal Justice, the National Center for Victims of Crime, the New York City Police Foundation, and the Ringling College of Art and Design.