Joel founded the Echoes, a group that specialized in British Invasion covers. When the Echoes became popular in New York, Joel left high school to become a professional musician. The Echoes began recording in 1965; Joel was originally hired by Snuff Garret as a pianist for Bobby Vee, however he was fired before doing any records or shows because he refused to wear the matching jackets the band was to wear. Joel (then 16) also played piano on several records released through Kama Sutra Productions and on recordings produced by Shadow Morton. Joel played on a demo version of Leader of the Pack, which would become a major hit for the Shangri-Las.
In late 1965, the Echoes changed their name to the Emeralds and then to the Lost Souls. Joel left the band in 1967 to join the Hassles, a Long Island group that had signed with United Artists Records. Over the next year and a half they released four singles and two albums (The Hassles and Hour of the Wolf). All were commercial failures. Joel and drummer Jon Small left the Hassles in 1969 to form the duo Attila, releasing an eponymous debut album in July 1970. The duo disbanded the following October when Joel began an affair with Small’s wife, Elizabeth, whom Joel eventually married.