Harline va abandonar l'estudi Disney el 1941 per compondre per altres estudis. Entre les bandes sonores compostes per ell es poden esmentar: "You were never lovelier" (1942) nominada a l'Oscar a la miller banda sonora, "The more the merrier" (1943), "Government girl" (1943), "Tender comrade" (1943), "Road to Utopia" (1945), "Johnny Angel" (1945), "The bachelor and the Bobby-soxer" (1947), "The boy with green hair" (1948), "Every girl should be married" (1948), "The big steal" (1949), "That's my boy" (1951), "His kind of woman" (1951), "Monkey business" (1952), "Pickup on South Street" (1953), "Broken Lance" (1954), "Good morning, Miss Dove" (1955), "The last frontier" (1955), "The enemy below" (1957), "Warlock" (1959), "These thousand hills" (1959) o "The wonderful world of Brothers Grimm" (1962).