 Based on the published evidence, collaborative care for depression is both necessary and sufficient for improving care and outcomes for depressed patients in primary care settings. The Translating Initiatives in Depression into Effective Solutions TIDES project, upon which ReTIDES is based, developed a VA-adapted version of collaborative care through input from veterans, clinicians, and managers. The initial TIDES project resulted in a clinically stable and effective model as tested in seven primary care practices in three VISNs. This positive result provided the basis for spreading and sustaining the TIDES model and initiating the study of national implementation strategies and issues. 