Stefan joined the Belgian Cystic Fibrosis Association as CEO in 2016 to professionalise and raise the impact of the association, in order to improve the lives of CF patients and their families. Newborn screening on CF was consequently implemented in 2019, followed by the reimbursement of new modulator therapies, Orkambi, Symkevi and Kaftrio between 2020 and 2022. In order to improve care and make the voice of patients with a rare condition heard, he joined the board of Rare Diseases Belgium (RaDiOrg) in 2018 and became chairman of the board in 2019. RaDiOrg represents all Patient Organizations in rare diseases and their patients on a national level. It was one of the driving forces behind the first National Rare disease plan and the setup of a national rare disease registry and represents the RD patient in several colleges, commissions and governmental health bodies. Stefan is also member of the Belgian CF Registry Board, secretary of the board of Cystic Fibrosis Europe and member of the Advisory Board of Pharma.be. He's an active contributor in several national and European policy initiatives and government bodies on rare diseases around diagnosis, Real World Data, ERN integration, registries, patient STA engagement and other topics.