This study investigated the influence of the situational characteristics of the drinking setting and a number of parental, personal and demographic variables on adolescents' alcohol use. The sample were 15-year-old participants in a multidisciplinary longitudinal study carried out in New Zealand. Measures of alcohol consumption were self reported amount of alcohol consumed on the most recent drinking occasion and amount usually consumed. All of the situational variables investigated had an effect on the amount of alcohol consumed on the most recent occasion. Greater amounts of alcohol were consumed if the alcohol was obtained from peers or by the 15-year-olds themselves, if the drink was consumed away from their own home, in the presence of peers only, and during the evening. More money to spend each week and lower SES were also associated with reports of greater alcohol consumption on the most recent drinking occasion. Adolescents with female friends who approved of drinking reported greater amounts of alcohol, the effect of female friends was most marked in the lower amounts reported by males who had female friends that disapproved of drinking. For amount of alcohol usually consumed, reports of larger amounts of alcohol were associated with more money available to spend each week and with lower SES. Furthermore, both males and females reported greater usual amounts if their male friends approved of drinking; female friends' approval was associated with greater amounts of alcohol usually being consumed, this effect was strongest for males. Sixty-eight per cent of the 15-year-olds indicated that they thought they definitely or probably would get drunk in the future.