His career in the entertainment industry began as a talent agent at the William Morris Agency in New York City. Minoff then moved to International Famous Artists. He rose to Vice President of the motion picture department at IFA. Minoff represented a number of notable figures during his fifteen years at the talent agencies, including Cicely Tyson, screenwriters Bruce Joel Rubin and David W. Rintels, and director Sidney Lumet. He also packaged several films, including the 1970 movie, Love Story and the 1971 blockbuster film, The French Connection. In 1974, Minoff left IFA and the talent agency business to become the president of David Paradine Television, which had been founded by journalist David Frost. While president of the company, Minoff teamed with television producer John Birt to co-executive produce The Nixon Interviews by Frost of Richard Nixon. The interviews, which took place three years after Nixon left office, were broadcast in syndication in 1977. The Nixon Interviews would later be adapted into a Broadway play, which in turn, formed the basis for the 2008 film Frost/Nixon, directed by Ron Howard, which was nominated for an Academy Award for Best Picture. Actor Keith MacKechnie portrayed Minoff in the film. As president of Paradine Television, Minoff also produced interviews with former Secretary of StateHenry Kissinger and the Shah of Iran, Mohammad Reza Pahlavi. Additionally, Minoff produced several television films for Paradine, including Dynasty and Portrait of a Rebel: The Remarkable Mrs. Sanger. Minoff left David Paradine Television in the early 1980s and worked for a time as an indie producer. In 1985, he partnered with actor and producer Mike Farrell to form Farrell/Minoff Productions, which created a series of made-for-TV movies. Minoff and Farrell would work closely together in a professional partnership for the next twenty-five years. Their many television movies featured such actors as Fred Savage, Ed Asner, Helen Hunt, Jill Clayburgh, Missy Crider, Patricia Wettig, and Tess Harper. Together, Minoff and Farrell produced two feature films. Their first film was 1988's Dominick and Eugene for Orion Pictures, which earned actor Tom Hulce a Golden Globe nomination for best actor. Farrell and Minoff later co-produced Patch Adams in 1998, which starred Robin Williams.
