Peak music experiences are those experiences involving music that stand out as especially affecting, meaningful and memorable for the individuals involved. They are a common topic in discussions of popular music, including in journalism, biography and fan culture, where they are often credited as pivotal in people’s relationships with music and their lives more generally. Examples of peak music experiences are apparent in some previous scholarly studies of popular music cultures, however, this is the first dedicated investigation of the phenomenon. By analysing this way of thinking and talking about music, this thesis contributes to understandings of how music’s meaning and effects are constructed, the role of musical experience in identity and sociality, and the discursive structuring of individual and collective experience in music scenes. The thesis draws on ethnographic research conducted in 2015 in the local music scene of Brisbane, Australia, including participant observation in activities of music consumption and production, reviews of secondary data sources including popular music media, and in-depth interviews. Interviews were conducted with 44 women and men between the ages of 23 and 58 who participated in Brisbane’s dance, hip hop, indie and rock ‘n’ roll music scenes. This research provides the basis for a grounded exploration of peak music experiences, as well as a contemporary ethnographic study of these scenes, demonstrating the methodological value of peak music experiences for music scene research. The findings are broadly divided into themes of identity and belonging. In the first part, peak music experiences are shown to be epiphanies through which self-narratives are constructed. This involves common tropes including first encounters, gateway experiences and conversion experiences, which offer discursive shape for the construction of identity through popular music and highlight common and divergent priorities between popular music cultures. In particular, these narratives enable and encourage people to present their relationship to music as personal, authentic, and aligned with specific cultural values. It is common for music scene participants to credit peak music experiences with inspiration and influence on their musical activities as well as other aspects of their lives. Analysing these claims highlights the crucial importance of affect in people’s responses to music and therefore its social agency. This analysis also responds to the important but under-explored question of why some people grant music a central status in their lives, as musicians, fans and in other roles, investing considerable resources and organising their social lives around it. Peak music experiences provide motivation to sustain social commitments and activities, as embodied experiences, memories and sought-after ideals. The second part considers the role of peak music experiences in belonging and collective identity. At the micro-social level, peak music experiences can both reflect and inform relationships between family, friends and romantic partners. At a larger scale, the music scene participants interviewed attributed peak music experiences most often to live and collective music events, reflecting the status accorded to these in both popular culture and scholarly research. These specifically celebrated instances of live music reveal what people value most in that context and how this differs between groups. Most notably, live music enables the exploration and celebration of individual and collective identity, including uncommon expressions of the self, resulting in especially affecting, memorable and meaningful musical experiences. Thus peak music experiences help to account for the special status of live music. Finally, the role of peak music experiences in music scenes is considered. Individuals’ peak music experiences contribute to and are shaped by collective memory in the Brisbane dance, hip hop, indie and rock ‘n’ roll music scenes. This informs ongoing practices in the scenes, which are defined partly by the shared priorities and ideals that are apparent in and reproduced by the peak music experiences of participants.