Although the American public health system has made major contributions to life expectancy for residents of this country over the past century, the system now faces more complex health problems that require comprehensive approaches and increased capacity, particularly in local and State public health agencies. To strengthen the public health system, concerted action is needed to meet these five critical needs: First, the knowledge base of public health workers needs to be supplemented through on-the-job training and continuing education programs. To this end, self-study courses will be expanded, and a network of regional training centers will be established throughout the country. Second, communities need dynamic leadership from public health officials and their agencies. To enhance leadership skills and expand the leadership role of public health agencies, focused personal leadership development activities, including a Public Health Leadership Institute, and national conferences will provide a vision of the future role of public health agencies. Third, local and State public health agencies need access to data on the current health status of the people in their communities and guidance from the nation's public health experts. To improve access to information resources, state-of-the-art technologies will be deployed to create integrated information and communication systems linking all components of the public health system. Fourth, local and State agencies need disease prevention and health promotion plans that target problems and develop strategies and the capacity to address them. To provide communities with structured approaches to this process, planning tools have been developed and distributed, and technical assistance will be provided to local and State health agencies to involve each community in planning,priority setting, and constituency building.Finally, public health agencies need adequate resources to fund prevention programs. To improve the use of existing Federal support and enhance the availability of new community resources, grant programs will be modified, and innovative approaches to local resource enhancement will be developed and shared.Activities in these five key areas are designed to improve the infrastructure of the public health system and its capacity to carry out effectively the core functions of public health assessment, policy development, and assurance of the availability of the benefits of public health. If the nation is to achieve the health objectives for the year 2000, the public health system-the individuals and institutions that, when working effectively together, promote and protect the health of the people-must be strengthened.