This is the report of an informal consultation which took place in Leysin, switzerland on 8–10 December 2003. The aims of the consultation were to provide WHO and Member States with evidence-based technical guidelines on the following aspects of P. vivax and P. falciparum epidemics: estimating the population at risk of malaria epidemics; forecasting and early warning systems for epidemic prediction; early detection systems for detection, verification and notification of malaria epidemics within two weeks of onset; and options for epidemic prevention and control.