The purpose of this study was to gain an in-depth understanding of how primary care practices in the United States are transforming their practice to deliver patient-centered care. The study used qualitative research methods to conduct case studies of small primary care practices in the state of Virginia. The research team collected data from practices using in-depth interviews, structured telephone questionnaires, observation, and document review. Team-based care stood out as the most critical method used to successfully transform practices to provide patient-centered care. This article presents 3 team-based care models that were utilized by the practices in this study.