Heat waves constitute an important public health problem because of their potential serious health impact on vulnerable populations such as the elderly and individuals living in poor health, socioeconomic, cultural or environmental conditions. The summer of 2003 was the hottest summer, with respect to both minimum and maximum temperatures, of the last fifty years. During that summer, an increased mortality was found especially in the elderly population = 75 years. The Ministry of Health therefore released guidelines for the regions and other local authorities, regarding the measures be undertaken in order to safeguard the elderly and other vulnerable populations from the health risks associated with heat waves. Subsequently, a survey was performed to collect information regarding the projects put into practice in the summer of 2004 by the various regions and local authorities. The aim of the study was to promote a comparison and sharing of appropriately documented experiences. This article classifies and describes the various interventions that were put into practice.