He specialized in robust action pictures, particularly westerns. He excelled at bringing to life tautly written stories about tough characters facing difficult circumstances. Conversely, just as often, he failed to redeem poorly written material, turning out an equally inadequate picture. Throughout his career he regularly alternated hits (such as Il giorno della vendetta (1959), I magnifici sette (1960), La grande fuga (1963), La notte dell'aquila (1976)) with misses (such as Il vecchio e il mare (1958), Ossessione amorosa (1961), Una ragazza chiamata Tamiko (1962), La carovana dell'alleluia (1965)). He has also been criticized for his lack of stylistic trademarks, though his best films remain exciting to watch.
