In the Islamic Republic of Iran, religion has traditionally played a central role in the lives of the people. Following the Islamic Revolution in 1979, it has also become integral to the country's governance. Since the Revolution, an exceptional synergy has arisen between the domain of religion and the health sector in the development of family planning policies, which have resulted in dramatic changes in population growth and fertility: the population growth rate decreased from 3.9% (1986) to 1.2% (2000) and total fertility from 6.8 (1984) to 2.1 (2000). The extraordinary aspect of this experience is that the position of religious authorities changed from one of opposition to one of active promotion of family planning. This paper describes the establishment and course of family planning programmes in Iran and makes use of interviews with two main protagonists of this experience (Dr Alireza Marandi -Minister of Health 1984Health -1989Health , 1993Health -1997; Dr Hossein Malekafzali -former Deputy Minister of Health). It is hoped that dissemination of this experience outside of the Islamic Republic of Iran will encourage the development of similar dialogue and synergy between religion and health in other countries. Flexibilité et pragmatisme dans la promotion de la santé : une expérience de synergie entre la santé et la religion en République islamique d'Iran RÉSUMÉ En République islamique d'Iran, la religion a traditionnellement joué un rôle central dans la vie de la population. Après la Révolution islamique de 1979, elle est aussi devenue partie intégrante de la gouvernance du pays. Depuis lors, une synergie exceptionnelle s'est dégagée entre le domaine de la religion et le secteur de la santé pour l'élaboration des politiques de planification familiale, ce qui a conduit à des changements radicaux en termes de croissance démographique et de fécondité : le taux de croissance démographique a diminué, passant de 3,9 % (1986) à 1,2 %