The chief federal agency responsible for the health of the United States consists of six major subdivisions: Alcohol, Drug abuse, and Mental Health Administration; Centers for Disease Control and Prevention; Food and Drug Administration; Health Resources Administration; Health Services Administration; and the National Institutes of Health. The major functions are 1. to assist states and communities with the development of health resources and to improve the development of education of health professionals; 2. to assist in the improvement of the delivery of public health services; 3. to conduct and support research in the medical and other health sciences; 4. to protect the nation against the importation and use of unsafe drugs and other potential health hazards; and 5. to protect against the spread of communicable diseases.