The Australian Government funds nationally focused school-based initiatives designed to address the increasingly important Science, Technology, Engineering and Mathematics (STEM) disciplines. The research project, Principals as STEM leaders – Building the evidence base for improved STEM learning – (PASL), is an additional activity funded under the National Science and Innovation Agenda (NISA) established in December 2015. In particular, PASL will contribute to NISA’s Inspiring all Australians in digital literacy and STEM measure. The research project has three workstreams. Workstream One – Research (including identifying best practice STEM leadership approaches) to inform development of professional learning modules/resources and a supporting mentoring approach for principals as STEM leaders. Workstream Two – Develop and pilot the professional learning modules and mentoring resources in this research project. Workstream Three – Over the life of the research project, monitor and evaluate the resources and supporting mentoring model developed under the research project to: a. determine those best practice approaches that increase principals’ STEM capabilities; b. result in high quality and accessible resources being available at the end of the research project.