British substance policy originated from international agreements which subsequently were incorporated into British law rather than in response to domestic need. Not until the 1960s did evidence emerge of a growing number of drug users. Legislation in the 1960s limited the prescription of certain drugs to clinic doctors and led to the creation of clinics for the treatment of addicts. The policy continues to be essentially punitive, and large numbers of people are dealt with by the courts for drug offenses. Emphasis is on law enforcement, but the policy includes education, treatment, and research. Four-fifths of enforcement activities involve cannabis which dominates the published statistics including those for imprisonment. The main elements of the current policy are firmly entrenched, and no substantial review is suggested for the foreseeable future. 37 references (Author abstract modified)