The purpose of this pilot/exploratory study is to identify and validate modifiable risk factors for nursing home acquired pneumonia that are amenable to a targeted prevention strategy. The underlying premise is that nursing home acquired pneumonia is a multifactorial geriatric syndrome with modifiable risk factors amenable to prevention. Under the standard disease model of pneumonia, the invading infectious organism is the focus of diagnosis and treatment. However, under the multifactorial geriatric syndrome model, the invading organism is the precipitating event which is superimposed upon a set of modifiable predisposing factors that make the individual vulnerable to infection with the invading organism. The specific aims of this pilot/exploratory study are to identify modifiable risk factors for nursing home acquired pneumonia in a development cohort of elderly residents (age > 65 years) housed in three New Haven area nursing homes, and to test the validity of the identified risk factors in an independent cohort of elderly residents housed in two additional New Haven area nursing homes. To accomplish these aims, baseline demographic and clinical data are being collected from enrolled residents, and surveillance for the primary outcome (radiographically documented pneumonia) is conducted three times per week for 12 months following enrollment. Bivariate and multivariable Cox modeling will identify modifiable risk factors that have an independent association with the development of pneumonia. Pneumonia is the leading cause of death in elderly nursing home residents, and it results in considerable morbidity and healthcare expenditures since it is a major cause of transfer to acute care facilities. The long term implication of this study is that identification and validation of modifiable risk factors for nursing home acquired pneumonia will facilitate the development of a targeted prevention strategy that can be tested and ultimately placed into practice to reduce the incidence of pneumonia in this vulnerable population of older Americans.