One hundred and twenty-two college students over a 2-week period completed a diary of their drinking habits and reasons for drinking, as well as a structured questionnaire about drinking attitudes and habits. Daily consumption based on the diary was compared with consumption based on a quantity-frequency measure within the questionnaire. There were no significant differences between estimates of consumption based on the two measures, and both measures were highly correlated. The questionnaire was more accurate in classifying drinkers and non-drinkers and led to better identification of those classified as hazardous and harmful drinkers. Sex differences in beliefs about drinking, as well as differences according to drinker classification, were found. Unsafe drinkers rated their drinking episodes as significantly more satisfying, comforting and exciting than other drinkers and were more likely to drink in order to get drunk and to relax. Their beliefs, attitudes and intentions also were more favourable towards the consumption of alcohol. Hotels or clubs were the most preferred locations for beer and spirits consumption while wine was consumed mainly at home. Most drinking took place within a mixed group or with close friends. Findings are discussed in terms of the relative advantages of both diary and quantity-frequency/questionnaire methods.