To assess the methods being used in US hospitals to prevent the spread of contagious illnesses from hospital employees to patients, we analyzed information obtained in the SENIC Project (Study on the Efficacy of Nosocomial Infection Control) from interviews with hospital officials and staff nurses. In general, staff nurses and their first-line supervisors appeared to be unfamiliar with some published recommendations outlining when an illness or exposure should exclude them temporarily from patient contact. The infection control nurse had authority to exclude employees in fewer than half of the hospitals. Although employees would be financially penalized in less than 10% of hospitals for missing work on account of a contagious illness, staff nurses in larger hospitals were more reluctant to consult the employee health service if they believed they would lose pay.