The incidence of pneumonia for elderly persons living in the community is 14 cases/1000 persons/y, whereas 33/1000 nursing home residents require hospitalization for pneumonia each year. Premorbid health status is more important than age in determining outcome from pneumonia in this age group. Two studies of mortality in the 2 years following pneumonia gave conflicting results. One study showed that the mortality rate was twice that which was expected. Both the clinical and radiographic diagnosis of pneumonia may be difficult in the elderly especially if there is co-existing congestive heart failure. Aspiration is an under-diagnosed cause of pneumonia in the elderly. Data from three randomized clinical trials indicate that intravenous antibiotic therapy can be changed to oral therapy when the patient has been afebrile (< 37.5 degrees C) for 16 hours, can take antibiotics by mouth, and has a leukocyte count returning towards normal. Adjunctive therapy with nutritional supplements and vitamin C may improve outcome in this group of patients. Yearly immunization with influenza A and B virus vaccine will reduce both the incidence of pneumonia and the rate of hospitalization for this infection. A discussion of pneumonia in the elderly is often divided into community-acquired pneumonia, which is treated at home or in a nursing home, or community-acquired pneumonia requiring hospitalization and nosocomial pneumonia. The latter is not described in this review.