 The pathogenesis of inflammatory bowel disease, IBD, involves a complex interplay between genetic, environmental, and microbial factors that disrupt the intestinal mucosal barrier, leading to increased permeability and triggering an immune response. IBD patients exhibit various defects in mucosal barrier components which may perpetuate chronic inflammation. Functional tests can assess gut barrier integrity, while TNF therapy and some probiotics have been shown to improve mucosal barrier function. However, further research is needed before permeability manipulation can be considered a viable therapeutic target in IBD. This article was offered by Andrea Michelin and Renata Dinka.