[Health Impact Assessments (HIA): an intersectoral process for action on the social, economic and environmental determinants of health].

Health Impact Assessment (HIA) is a practice that has grown in popularity worldwide, since the end of the 1990s. Originally used in the framework of Environmental Impact Assessments (EIAs), HIA has become enriched through the addition of knowledge and principles based on the social determinants of health and the tackling of health inequalities, and has been brought to bear on the policy-planning process at all levels of government. HIA has three overlapping objectives: to assess the potential effects of a policy on health, to encourage citizen and stakeholder participation in the impact analysis process, and to inform the decision-making process. This article briefly defines HIA; defines its standardized process in successive steps, which allows users to give structure to their actions and to establish the steps to be followed (detection, framing, analysis, recommendations and evaluation); and offers three examples of HIA in three different situations: the Geneva canton of Switzerland; Rennes, France; and in the Montérégie region of Quebec, Canada. Together, these illustrations show that HIA is a promising strategy to influence local decisions and to integrate health into projects and policies at the local and regional levels.