Health activities carried out in 1975 by NIOSH under the Federal Coal Mine Health and Safety Act of 1969 were described. Activities included periodic medical services for coal miners, extensive research in pulmonary diseases, setting occupational standards in coal mining industrial health programs, and paying for postmortem examinations of miners and former miners. The medical services included physical examinations, chest x-ray examinations for working miners, and postmortem studies of other miners. Of 56,575 men participating in the second round of chest x-ray examinations between July of 1973 and March of 1975, lung cancer was suspected in about 750 of them, marked emphysema was noted in more than 3,500, and evidence for tuberculosis, usually inactive, was noted in more than 3,000. Research designed to improve the health of coal miners was divided into five major areas: early diagnoses, epidemiological studies, infectious disease studies, laboratory investigations, and toxicologic studies. The major epidemiological study was devoted to coal workers' pneumoconiosis. Infectious disease research was directed toward evaluating the interactions of mineral dusts and infectious agents, assessing miner susceptibility, and developing the techniques for identifying and treating persons who are or who might become susceptible to repeated respiratory tract infections. Interagency activities have involved the Food and Drug Administration, the Department of Labor, the Coal Mine Health Research Advisory Committee, the Interim Compliance Panel, and the Department of the Interior.