With his brother, producer-director Joseph Cates, he produced Spoon River Anthology on Broadway, then in London, and later for television. In 1962, Cates made a short film, The Painting, followed by his first feature directing effort, Rings Around the World. He produced and directed the 1970 film version of the Broadway hit I Never Sang for My Father, which earned three Academy Award nominations. His 1973 film, Summer Wishes, Winter Dreams, received two Oscar nominations. Other directing credits include The Promise; One Summer Love; The Last Married Couple in America; Oh, God! Book II; and Backfire.
Cates distinguished himself as director and/or producer of many acclaimed television dramatic specials and movies like the Emmy Award-winning To All My Friends on Shore. Other television credits include After the Fall; Johnny, We Hardly Knew Ye; Consenting Adults (for which he was Emmy-nominated for directing); Fatal Judgment; Do You Know the Muffin Man (Emmy nominated for directing); the DGA Award-nominated Call Me Anna; Absolute Strangers (Emmy nominated for directing); In My Daughter's Name; Tom Clancy's Netforce; and Collected Stories for PBS. Cates produced his first Academy Awards telecast in 1990, receiving an Emmy in 1991 and twelve subsequent Emmy nominations as the show’s Producer, as well as a 2005 Golden Laurel nomination from the Producer’s Guild. In addition to producing the Oscars, Cates currently serves as Producing Director of the Geffen Playhouse, founded the UCLA School of Theatre, Film and Television, and served as Dean of the school.
Cates joined the DGA in 1960 and was elected to the National Board in 1975, serving as President from 1983-1987 and as Secretary-Treasurer from 1997-2011. He also served on the Eastern Directors Council from 1975-1979, the Western Directors Council from 1982-2011 and was a member of the six Negotiating Committees, serving as Chair for the 2002, 2005, 2008 and 2011 cycles. He spearheaded the DGA's efforts against colorization of black and white films, which led to the National Film Preservation Act of 1988. In 1989, Cates received the Robert B. Aldrich Award for extraordinary service to the Guild, followed in 1991 by the DGA Honorary Life Member Award, and in 2005 by the DGA President's Award. In addition to his service to the Directors Guild, he was a member of the Board of Governors of the Academy of Motion Picture Arts and Sciences, Directors Branch and received the 2005 American Society of Cinematographers Board of Governors Award.