Recent research on lifestyle sport and commercialization reveals a problematic and complex relationship. The analysis presented here examines the development and impact of commercialization on a unique and influential local BMX scene over a 20-year period. Three forms of commercialization - paraphernalia, movement and mass market - are identified and their varying influences on the mobilization and development of this lifestyle sport are analysed. Findings reveal that lifestyle-sport insiders actively collaborate in each form of commercialization, especially movement commercialization which has the potential to build alternative lifestyle-sport institutions and resist adverse commercial influences. This research conceptualizes freestyle BMX as a social movement within the resource-mobilization perspective and relies upon a combination of direct and participant observation recorded through field notes and augmented by 25 in-depth interviews. The combination of analytical tools and methodological approach can help shed further light on the complex dynamics of commercialization in lifestyle sports.