In traditional geriatric medicine, comprehensive assessment is considered crucial to the care of frail older patients. The principles of geriatric assessment--identifying high-risk patients and targeting them for preventive interventions--are also practiced by managed care organizations (MCOs). Self-reported health surveys and administrative data are two methods used by MCOs to identify members at high risk for adverse health outcomes and functional decline who may benefit from geriatric case management. For a successful partnership with primary care physicians, it is very important that geriatric care managers should be knowledgeable in the principles of geriatric medicine.