The purpose of this study was first to compare 18-19-year-old male abstainers with alcohol consumers, and especially light consumers, regarding degree of sociability as indicated by their (in)security in the company of others, their number of close friends, intimate conversations with friends and their popularity in school. Secondly, we analysed the importance of antecedents to and covariates of abstinence. In addition, the significant antecedents and covariates gave us information as to abstinence patterns. The study was based on a survey of all Swedish males, 18-19 years old, conscripted for military service in 1969-70. Data had been collected by means of questionnaires and psychological interviews, giving measures of each respondent's social background, psychiatric/psychological and psychosomatic health status, substance use, deviant behaviour and degree of sociability. Poor sociability was more common among the abstainers than among all the other categories of drinkers, including the light consumers. The conscripts' social background, and especially their fathers' drinking habits, had the strongest effects in explaining abstinence. Sixty-two per cent of all abstainers had non-drinking fathers, compared to 28% of the light consumers. As to the majority of abstainers, this indicates a link between the social background of temperance and their own reported abstinence. Their poor sociability could be a consequence of abstaining at a young age when abstinence is uncommon. Those who abstained despite a drinking father showed a worsening psychological status, suggesting a link between psychologically impaired health, poor sociability and abstinence. Though the abstainers were the least sociable, the difference between the abstainers, the light consumers and the moderate consumers in other categories were generally small.(ABSTRACT TRUNCATED AT 250 WORDS)