Generic prescribing is steadily increasing, a change which we and others encourage. The proportion of prescriptions written in general practice in England using the generic (approved) name increased from 35% in 1985 to 55% in 1995. Where a product is prescribed generically, the alternatives that could be supplied should be equivalent, to ensure that patients are not put at risk. In this article, were view how the equivalence and quality of generic drugs are assured and consider whether the process is adequate.