With the demise of the swing era and the decline of the great touring big bands, a major change in jazz music occurred. The advent of bebop led to new developments in Fitzgerald's vocal style, influenced by her work with Dizzy Gillespie's big band. It was in this period that Fitzgerald started including scat singing as a major part of her performance repertoire. While singing with Gillespie, Fitzgerald recalled, "I just tried to do my voice what I heard the horns in the band doing."