The World Food Summit, held in Rome in November 1996, recognised the urgent need for better information. As a result the FIVIMS (Food Insecurity and Vulnerability Information and Mapping System) initiative was launched, as a co-operative venture, to assist countries and the international community to identify the "who, where and why" of food insecurity. Even before the Summit, many countries had established approaches for this purpose based on multidisciplinary networks, at national and local levels. One of these approaches, developed first in French-speaking Africa, is the FSIEWS method (Food Security Information and Early Warning System) proposed in this handbook as one of the tools available to those engaged in the fight against hunger. This contribution to the FIVIMS initiative is addressed to the national technical officers at central and decentralised level, as well as to their collaborators from the technical assistance community.