While investment in water safety education appears sound, little is known about how youth construct their understanding of water safety principles and what formative influences impact on their beliefs and practices. Year 11 students (n = 2,202) from 41 high schools took part in a nationwide survey on youth water safety knowledge, attitudes, and behaviors. The self-completion written questionnaire was undertaken in school time in the second term of 2003. Data were analyzed using a range of sociodemographic variables, including gender, socioeconomic status and ethnicity. The formative influence of peers, family, and schooling on the water safety of youth who took part in the study varied considerably. Several key findings suggest that males construct their understanding of water safety and drowning risk differently from that of females. Notably, ten times as many male youth identified peers as the primary source of water safety understanding; however, males reported observing much higher incidence of unsafe practice among their friends. Females were more likely to identify parents and schools as their primary source of water safety knowledge. Ways of addressing these differences are discussed.