Present trends suggest that many of the poorest countries in the world, including many in sub-Saharan Africa, will not meet the health-related Millennium Development Goals (MDGs), especially MDG 4 (reducing under-five mortality) and MDG 5 (reducing maternal mortality). Even in those countries that are on track to meet health MDGs, striking inequities exist among countries and among socioeconomic groups within them, despite effective and cost-effective interventions being available to improve population health, including that of vulnerable groups.