Parental guidance concerning alcohol was explored using data from a 2007 survey of 2179 UK school students aged 15 and 16 years. Cluster analysis based on questions about parental advice was used to establish seven student groups. Associations between groups, other family background and psychoactive substance use variables were explored. Substance use was least common amongst students whose parents discouraged drinking and those who claimed to have received no parental guidance. The heaviest substance users were teenagers from families with more favourable, tolerant attitudes to alcohol and intoxication and among students who failed to answer the questions about parental guidance. These scored highly on cannabis and other drug use. The cluster in which there was comprehensive discussion with the parents about alcohol use had an intermediate position in relation to substance use. In logistic regressions parental guidance was consistently associated with substance use with several other background variables controlled. (Contains 6 tables.)