Robert "Red" Ginzler (20 July 1910, Leechburg, Pennsylvania – 29 December 1962, New York) was an American orchestrator, principally remembered for his contributions to the landmark Broadway shows Gypsy, Bye Bye Birdie and How to Succeed in Business Without Really Trying. A frequent collaborator with fellow arrangers Sid Ramin and Don Walker, he was also billed as Seymour Robert Ginzler until his heyday in the late 1950s.