Mancuso started as an usher in a theater in Buffalo, New York[3] and eventually ran the programming for the company's 50 theatres.[1]
Mancuso joined Paramount Pictures in 1962, booking films from their Buffalo office. He worked his way up through their sales division before becoming vice-president of domestic distribution in March 1977. He became senior vice-president in August 1978. In April 1979, he was promoted to executive vice-president for distribution and marketing taking over marketing responsibilities. In August 1980, he became president of Paramount's new Distribution division which also became responsible for acquiring films for distribution.[4]
In March 1991, Mancuso left Paramount soon after Stanley Jaffe had joined and filed a $45 million lawsuit for breach of contract.[3]
In 1993, Mancuso became chairman and CEO of Metro-Goldwyn-Mayer until his retirement in 1999.[3] He is currently the chairman of the Motion Picture and Television Fund Corporate Board of Directors.