To explain rising rates of sexually transmitted infections it is necessary to monitor trends among high risk groups, such as youth. Surveillance of risk behaviours and testing among a variety of populations in different settings is required. We monitored self-reported sexual behaviour among music festival attendees.

Cross-sectional studies of young people's behaviour were conducted annually at a music festival between 2005 and 2008 using self-administered questionnaires. Logistic regression, adjusted for age and gender, determined trends in risk behaviours.

More than 5,000 questionnaires were completed. The proportion reporting multiple sexual partners in the past year remained stable from 2005 to 2008 and condom use with these partners increased. Reporting a new sexual partner in the past three months decreased, while condom use with new partners increased. Reporting a casual sexual partner increased and condom use with casual partners remained stable. Reporting a recent STI test increased from 23% in 2006 to 32% in 2008.

Despite increases in STI notifications, most risk behaviours are decreasing in this group, possibly as a function of increased STI testing. Music festivals are a useful setting for monitoring behaviour trends within a sub-population of young people at relatively high risk of STIs.