Surveillance of infectious episodes in institutionalized elderly men permanently resident on two wards of a veterans' hospital was undertaken for a 12-month period. One-hundred eleven episodes were identified in 50 residents (74 per cent). The most frequent infections included lower respiratory tract infections (incidence 59/100 patient-years), febrile episodes with no source (43.4), skin and soft tissue infections (36.5), and gastroenteritis (33). Only pneumonia was associated with significant mortality. A specific etiologic agent was seldom identified other than for skin and soft tissue infections. Antimicrobial therapy was prescribed for 87 per cent of all infections. Ward staff absenteeism was associated with peak occurrences of infections in residents. Resident characteristics that correlated with infection were incontinence of bladder and of bowel. Mental status or degree of mobility did not correlate. While infections occur frequently in this population, mortality is common only with pneumonia. Infections occur more frequently in residents who have greater functional impairment.