At one time a literary agent who represented such writers and directors as John Badham, Paul Brickman, Alvin Sargent and David Seltzer, Rosenberg joined Warner Bros. as a vice president in the studio's production division in 1978. Five years later he became president of production worldwide, developing and overseeing "The World According to Garp", "Never Say Never Again (both 1983), "The Killing Fields" and "Greystoke: The Legend of Tarzan, Lord of the Apes" (both 1984). Rosenberg left Warner Bros. after seven years and soon thereafter partnered with Sydney Pollack at Mirage Enterprises, a