Koen is the Founder and Chief Executive Officer of Beneficial Microbes® Consultancy, as well as Beneficial Bugs B.V., and serves as Chief Scientific Officer of the spin-off company InnerBuddies. He is also the initiator and co-organiser of the Beneficial Microbes Conference series and editor-in-chief of the journal Beneficial Microbes. In his university group the effect of food components on health and disease through the gut microbiota are studied using sophisticated in vitro models of the gastrointestinal tract.