Some managed care organizations (MCOs) serving Medicaid beneficiaries are actively engaging in community partnerships to meet the needs of vulnerable members and nonmembers. We found that the history, leadership, and other internal factors of four such MCOs primarily drive that focus. However, external factors such as state Medicaid policies and competition or collaboration among MCOs also play a role. The specific strategies of these MCOs vary but share common goals: 1) improve care coordination, access, and delivery; 2) strengthen the community and safety-net infrastructure; and 3) prevent illness and reduce disparities. The MCOs use data to identify gaps in care, seek community input in designing interventions, and commit resources to engage community organizations. State Medicaid programs can promote such work by establishing goals, priorities, and guidelines; providing data analysis and technical assistance to evaluate local needs and community engagement efforts; and convening stakeholders to collaborate and share best practices.