Stefan Sleijfer is Chairman of the Executive Board of Erasmus MC and Dean of the Faculty of Medicine and Health Sciences at Erasmus University Rotterdam. 

He studied medicine at the University of Groningen and then obtained his doctorate from the same university. He did his training as an internist-oncologist at Erasmus MC. Since completing his specialization in 2004, he has been working as an internist-oncologist at Erasmus MC. He was appointed professor in 2011 and head of department in 2013. From 2017 he was also theme chairman of Thema Daniel den Hoed.