The Handbook on the Pharmacovigilance of antimalarial medicines is a detailed manual giving a step by step approach to undertaking the pharmacovigilance of antimalarials. It is intended to be a source of practical advice for Pharmacovigilance Centres. It provides information on spontaneous reporting of adverse drug reactions as a complement to other WHO publications. In addition, it provides details on how to conduct cohort event monitoring, which is a method of active safety surveillance collecting information on all adverse events occurring after treatment. It also details how to perform causality assessment and signal identification, applicable to both methods of surveillance.