Europe, with its 53 countries and divided history, is a remarkable but inadequately exploited natural laboratory for studies of the eff ects of health policy. In this paper, the fi rst in a Series about health in Europe, we review developments in population health in Europe, with a focus on trends in mortality, and draw attention to the main successes and failures of health policy in the past four decades. In western Europe, life expectancy has improved almost continuously, but progress has been erratic in eastern Europe, and, as a result, disparities in male life expectancy between the two areas are greater now than they were four decades ago. The falls in mortality noted in western Europe are associated with many different causes of death and show the combined eff ects of economic growth, improved health care, and successful health policies (eg, tobacco control, road traffic safety). Less favourable mortality trends in eastern Europe show economic and health-care problems and a failure to implement effective health policies. The political history of Europe has left deep divisions in the health of the population. Important health challenges remain in both western and eastern Europe and signify unresolved issues in health policy (eg, alcohol, food) and rising health inequalities within countries.