Data collected in the 1985 National Nursing Home Survey were analyzed to identify risk factors for infections and mortality and to explore their relationship in US nursing homes. An infection was recorded in 166,609 (14%) discharges. Risk of pneumonia was found to be higher among bedbound patients (54.5 vs 13.1 per 100 discharges); urinary tract and other infections were most frequent among residents with indwelling catheters (6.6 vs 1.0 per 100 discharges). Residents with pneumonia were more likely than those with other infections to die (35% vs 28%), or be discharged to hospitals if alive (94% vs 66%). Thus, immobility and catheterization were associated with infections in US nursing homes, and pneumonia was found to contribute to mortality.