The global community is in the midst of a growing response to health crises in developing countries, which is focused on mobilising financial resources and increasing access to essential medicines. However, the response has yet to tackle the most important aspect of health-care systems--the people that make them work. Human resources for health--the personnel that deliver public-health, clinical, and environmental services--are in disarray and decline in much of the developing world, particularly in sub-Saharan Africa. The reasons behind this disorder are complex. For decades, efforts have focused on building training institutions. What is becoming increasingly clear, however, is that issues of supply, demand, and mobility (transnational, regional, and local) are central to the human-resource problem. Without substantial improvements in workforces, newly mobilised funds and commodities will not deliver on their promise. The global community needs to engage in four core strategies: raise the profile of the issue of human resources; improve the conceptual base and statistical evidence available to decision makers; collect, share, and learn from country experiences; and begin to formulate and enact policies at the country level that affect all aspects of the crisis.