Mr. Liff was one of the last of a breed of independent-minded super agents who once dominated the Broadway universe, fashioning high-profile deals with a lunch, a call or a handshake. His many famous clients once included Chita Rivera, Angela Lansbury and Ellen Burstyn.

He was also a producer, with a good eye for quality, often groundbreaking work. His producing credits stretch back to The Road of the Greasepoint—The Smell of the Crowd in 1965. Other shows in which he was an associate producer included Inadmissible Evidence, Cactus Flower, Marat/Sade, Philadelphia, Here I Come!, Don’t Drink the Water; Rosencrantz and Guildenstern Are Dead; The Happy Time; Play It Again, Sam; Child’s Play; Moonchildren; Sugar and Tricks, in 1973, his final producing credit.

He began his career in the theatre as a stage manager, working on Along Fifth Avenue in 1949. He was also stage manager or production stage manager on Gentleman Prefer Blondes, My Fair Lady, The Matchmaker, Moby Dick and many more shows. He frequently worked for notorious producer David Merrick. In the 1970s, he left behind producing to become an agent, joining the William Morris Agency.

As an agent, he also represented the estate of Eugene O’Neill and was reportedly single-handedly responsible for bringing the Kevin Spacey revival of The Iceman Cometh back to Broadway.

Mr. Liff’s nephew Vincent Liff, who would grow up to become a powerful Broadway casting agent, would often spend his days running around Biff Liff’s offices, soaking in the theatrical atmosphere. In 2006, the elder Liff was awarded Tony Honors for Excellence in the Theatre..