Tight junctions are dynamic structures that may undergo structural and functional changes in response to both physiological and pathological circumstances. Several microbial pathogens impair intestinal barrier function by exploiting tight junctions. These pathogens have developed a broad and complex range of strategies to subvert host tight junction barrier function. The purpose of this review is to give an overview of the mechanisms whereby select enteric viruses, bacterial pathogens and parasites modulate intestinal tight junctional structure and function and how these effects may contribute to the development of chronic intestinal disorders.