Interdisciplinary care management is advocated for optimal care of patients with many types of chronic illnesses; however, few models exist that have been tested using randomized trials. The purpose of this report is to describe the theoretical basis for the After Discharge Management of Low Income Frail Elderly (AD-LIFE) trial, which is an ongoing 2-group randomized trial (total n ¼ 530) to test a chronic illness management and transitional care intervention. The intervention is based on Wagner's chronic illness care model and involves comprehensive posthospitalization nurse-led interdisciplinary care management for low income frail elders with chronic illnesses, employs evidence-based protocols that were developed using the Assessing Care of Vulnerable Elders (ACOVE) guidelines, emphasizes patient activation, and integrates with community-based long-term care and other community agencies. The primary aim of the AD-LIFE trial is to test a chronic illness management intervention in vulnerable patients who are eligible for Medicare and Medicaid. This model, with its standardized, evidence-based medical and psychosocial intervention protocols, will be easily transportable to other sites interested in optimizing outcomes for chronically ill older adults. If the results of the AD-LIFE trial demonstrate the superiority of the intervention, then this data will be important for health care policy makers.