Sebastiaan Steenman is director of the undergraduate school and member of the board of the Utrecht University School of Governance, and Senior Fellow of the Centre for Academic Teaching and Learning (CAT). He teaches courses in methods and statistics, political philosophy, public policy, and organisation science. He also supervises theses. 

Sebastiaan chairs the national Expertgroup for the Accessibility of Higher Education (ETHO), which is part of NWO/NRO. He is a member of the assessment committee for the University Teaching Qualification of the faculty of Law, Economics and Governance (LEG), and project leader for the initiation of a university-wide Skills Academy. He is a member of the programme board of the Utrecht University strategic theme Pathways to Sustainability where he has the education portfolio, and he is a member the leadership of the community Sustainability Education and Engagement.

Sebastiaan is interested in education policy and his research focuses on selective admission to higher education and the development of skills, including cognitive skills. He was project leader of Select-UU (2018-2023), a project aimed to further improve selective admissions practices at Utrecht University in both the undergraduate and graduate phase. This project also resulted in the Handbook Selection Higher Education.