Herbert began to compose operettas in 1894, producing several successes, including "The Serenade" (1897) and "The Fortune Teller" (1898). Some of the operettas that he wrote after the turn of the 20th century were even more successful: "Babes in Toyland" (1903), "Mlle. Modiste" (1905), "The Red Mill" (1906), "Naughty Marietta" (1910), "Sweethearts" (1913) and "Eileen" (1917). After World War I, with the change of popular musical tastes, Herbert began to compose musicals and contributed music to other composers' shows. While some of these were well-received, he never again achieved the level of success that he had enjoyed with his most popular operettas.