Since the precautionary principle becomes a burning public issue at times of major crises, it meets critical social demands for safety and information. However, extending the precautionary principle to all areas of healthcare raises specific questions stemming from the complexity of the expectations people have for care and health, and from the special character of individual or group healthcare actions. The conditions governing the application of the precautionary principle to health, its possible translation into law, its impact on the public administration of health hazards and its necessarily international scope means that this issue falls under political responsibility and decision-making.