ABSTRACT. The contribution of drug utilisation studies on national, regional and local levels, to the quality control or audit of drug therapy is discussed. Two major types of audit, self‐audit and peer‐group audit, are outlined and examples presented illustrating how the concept of audit may be applied to therapeutics with special reference to drug information centres, feedback of drug prescribing data, and drug formularies. When drug information on prescribing practice from these sources is disseminated to the prescribers without value judgements being made, the component of self‐audit is predominant in contrast to drug information dealing with prescribing appropriateness, in which peer‐group opinion is expressed. Methods of capturing and disseminating data on prescribing practice which could be used in the auditing process are described. However, the greatest contribution to therapeutic audit lies with those responsible for medical training who should foster the quality of selfcriticism and the quest for high standards of prescribing practice in their students.