The concept of external criticism has been associated with different aspects of Obsessive Compulsive phenomena. The various threads of evidence highlight the potential role of criticism within different areas of the cognitive model of Obsessive Compulsive Disorder (OCD) with often overlapping ideas. However, the fragmented nature of the findings makes it difficult to identify how or why criticism impacts on OCD. This review collates the existing findings and maps these onto the cognitive model of OCD to provide a better understanding of the potential role of criticism. It proposes criticism could play a role in OCD as a vulnerability factor, but also as a perpetuating factor. Furthermore potential research questions have been generated which could help inform future understanding. Future research should consider the complexity of the concept when defining criticism as well as developing methodological designs which could answer questions of causality.