This study evolved from concerns about the number of young people drowning in New Zealand (544 deaths between 1980-1994), the author’s long experience with surf life saving and the suspicion that participation statistics on aquatic recreation do not adequately explain why so many young people drown. It was postulated that the risk of drowning associated with aquatic recreation also was the consequence of many underlying water safety influences that operate at intrapersonal, interpersonal and community levels. Thus the purpose of the study was to obtain comprehensive data on what young people know, think and do about their safety during aquatic recreation. A 25-item questionnaire was designed to survey a randomised sample of New Zealand youth (2202, year 11, 15 – 19 year olds) to assess their participation in, knowledge about and behaviour during aquatic recreation. To develop the questionnaire, a conceptual framework was devised that constructed the risk of drowning as a complex phenomenon dependent on how often young people participate in various forms of water-based activities, but largely influenced by their water safety knowledge, attitudes and behaviour, all of which are shaped by social, cultural and demographic variables. Almost all New Zealand youth had taken part in some swimming (98%) or other aquatic activity (94%) in the previous year. Risk of drowning was exacerbated among many students because they had poor water safety skills and knowledge, held unsound water safety attitudes, and often practiced at-risk behaviours. For example, many students estimated that they could not swim more than 100 m (54%), thought that swimming was acceptable at a surf beach after patrol hours (61%), and had swum outside patrol flags (61%) or never worn lifejacket (19%) during aquatic recreation. Taken separately, any one of these dispositions is capable of heightening drowning risk; taken collectively they offer strong explanation as to why youth are at greater risk of drowning than others. When analysed by gender, the lack of water safety knowledge, the prevalence of unsafe attitudes and at-risk behaviours among males was consistent and pronounced. The effect of socio-economic status and ethnicity on these risk-enhancing dispositions was less pronounced, although the data did suggest that the knowledge base of youth from low-decile schools and of Pasifika and Asian ethnicity provided least protective potential in the event of unintentional submersion.