He wrote the screenplays for 37 movie he directed, many of which are today known as classics such as; "The Maltese Falcon" (1941), "The Treasure of the Sierra Madre" (1948), "Key Largo" (1948), "The Asphalt Jungle" (1950), "The African Queen" (1951), "Moulin Rouge" (1952), "The Misfits" (1961), and "The Man Who Would Be King" (1975).