The University of Texas System includes thirteen academic and health institutions serving more than 256,000 students. This planning project, referred to as Texas-Plan, focuses on defining the full set of opportunities for a University of Texas System Open-Source Program Office (Texas-OSPO). The intent is to scope how such an office could function as a center for open-source activity, training, connections, and support, enabling open-source practices to become an integrated part of the missions of UT System institutions. Project activities center on requirements gathering and coordination across participating sites. The planning process involves the existing OSPO at The University of Texas at Austin, along with partners from The University of Texas at Dallas, The University of Texas at El Paso, and The University of Texas at San Antonio. Work includes assessing partner needs and capabilities, exploring how activities could be better coordinated across institutions, and considering the potential inclusion of additional system members. The project draws on current UT Austin OSPO efforts, including training, best-practice documentation, and consultation services, to inform possible future directions. By fully understanding institutional differences and shared needs, the planning effort aims to outline a sustainable approach for a potential system-wide open-source program office.