This conceptual paper critically explores the construct of agency from a dissertation research supervisor perspective. While the literature has expanded in the exploration of student agency, little focus has been given to the construct from a research supervisor agency stance. While current research into doctoral completion has shown the relationship between supervisor and dissertation writer as critical to persistence and completion, less investigation has focused on the aspects of dissertation supervisor agency and the evolution to a high mentoring approach especially for online doctoral students. The inquiry utilizes the lens of Lave and Wenger's situated learning theory to view how dissertation research supervisor agency can foster and guide doctoral scholars to consider researcher positionality and move from the margins of the doctoral learning community to the center of scholarly life and post-doctoral practice-based research and evidence-based decision making.