Data from the National Occupational Exposure Survey were examined to assess compliance with the Occupational Safety and Health Act of 1970 requiring employers to maintain records of workplace injuries and illnesses. Of the 4,185 companies with 11 or more employees that were surveyed, 3,142 (75.1 percent) maintained OSHA Form 200, an annual log and summary of injuries and illnesses. The number of employees and the presence of a union were positively associated with record maintenance; of the 665 companies with 500 or more employees, 95 percent maintained records, while of the 2,313 companies with 11 to 99 employees, 61 percent maintained records. Of the 1,808 companies with unions, 84 percent maintained records, as opposed to 69 percent of those companies without unions. Ranking of Standard Industrial Classifications by degree of compliance indicated that transportation equipment, petroleum refining, and primary metal industries had the highest proportions of compliance; highway passenger transportation, personal services, and automotive repair and service industries had the lowest proportions. Companies which were established before the 1970 Act maintained OSHA logs more frequently than did those which were established after the Act. The authors conclude that the failure to maintain logs indicates that many workers are not being informed about workplace injury and health risks; noncompliance may reflect the absence of other elements of safe and healthful work environments.