1 The clinical pharmacologist in drug regulation has many roles to play. These include responsibilities for the premarketing assessment of a new product's efficacy and safety, for scrutiny of the summary of Product Characteristics, and for monitoring its performance after marketing. Furthermore, the clinical pharmacologist has a subsidiary responsibility in examining the results of preclinical pharmacological and toxicological studies. 2 Clinical pharmacologists in regulatory authorities have one further, and crucial, responsibility-humility. From their training and experience they will (or should) know of their own scientific limitations and of the necessity for seeking help and advice from other disciplines.