This chapter considers the relationship between youth and music as this has been represented and theorised since the 1950s. The first section of the chapter examines the socio-economic circumstances that gave rise to the mass production of popular music during the post-Second World War era and the way it was marketed as a ‘youth’ leisure form. This is followed by an examination of studies that interpret the significance of popular music for youth in terms of its cultural resonance with issues such as class struggle, economic inequality and racism. Attention then turns to a consideration of work which, influenced by postmodernism and the cultural turn, has sought to position popular music’s significance for youth not as a direct reflection of socio-economic experience but rather as a cultural resource that supplies young people with agency in the construction of reflexive identities and lifestyles. The final section of the chapter considers the problem of defining the cultural relationship between ‘youth’ and music in the context of the early twenty-first century when the audiences for music once deemed the exclusive purview of youth are increasingly multi-generational.