Anticipated Impacts on Veterans Health Care: This proposal supports a funded SDP to improve anticoagulation care. The funded SDP developed a provider-level implementation strategy. However, preliminary formative evaluation indicates that differences among medical centers impacted the degree of support middle managers (i.e., chiefs of pharmacy) provided to the intervention. The proposed RRP will support the tailoring of the SDP and provide the knowledge needed to conduct a national implementation of this SDP intervention by developing an implementation strategy that accounts for differences in medical centers. More broadly, understanding how and why middle managers may or may not support interventions is critical knowledge for implementation science that may indirectly impact Veterans health care. Project Background: Anticoagulation (AC) with warfarin is effective in preventing thromboembolic events, particularly strokes. An anticoagulation intervention has been funded by the Stroke QUERI. Preliminary results are positive, but some sites are encountering medical center-level implementation barriers. Specifically, the research team has encountered barriers to engaging Chiefs of Pharmacy in the intervention, despite the support of the network director. This is a concern both for the current intervention, but also more generally for the success of future QUERI interventions. Understanding how differences between medical centers impact implementation requires additional analyses that are outside the scope of the original SDP. Project Objectives: The purpose of the proposed grant is to develop a medical center-level implementation strategy for the SDP intervention. The knowledge collected in this RRP regarding how differences in the context of medical centers impact whether chiefs of pharmacy support the intervention will serve as preliminary data for a future SDP to study the national roll-out. This RRP will answer three research questions. First, how can middle manager support influence implementation of the AC/TTR intervention? Second, what organization context factors influence the engagement of middle managers? Third, what factors can serve as an impetus to promote engagement of senior and middle managers? Project Methods: Our preliminary hypothesis, based on the SDP formative evaluation, is that differences in context affected implementation by impacting how and to what extent chiefs of pharmacy supported the intervention. We will build on the formative evaluation interviews with chiefs of pharmacy and conduct additional interviews for eight chiefs of pharmacy, their eight supervisors, and approximately eight pharmacy executives from VISN 1 and Pharmacy Benefits Management. We will carry out a qualitative thematic analysis to analyze interviews using the Organizational Transformation Model conceptual framework to refine the preliminary hypothesis by identifying what dimensions of context might have impacted implementation.