After a 12-year career in international higher education and development cooperation, Willem-Jan started working in the field of volunteer policy & management and civil society development in 2005 at the national Dutch institute for social development. In 2019, he established his own social enterprise. He works as consultant, trainer, researcher and writer for individual volunteer involving organisations, educational institutes & research centres, volunteer centres and (inter)national programmes targeted at enhancing volunteering and civil society engagement in the Netherlands and Europe. Throughout his career, his drive has been to help civil society organisations, volunteer managers, community leaders and volunteers to move into the direction that will give them the best chance to flourish. Currently, he works as member of the management teams of the national programmes Growing Older Together and Volunteering More and Differently. He is responsible for applied research, coaching local staff and for learning & development. He is co-author of the fifth edition of the Dutch Handbook Working with Volunteers (2025). He gives lectures in postgraduate education programmes of Pons Academie and Erasmus University Rotterdam.