This study reviews research on the construct of intolerance of uncertainty (IU). A recent factor analysis (Journal of Anxiety Disorders, 25, 2012, p. 533) has been used to extend the transdiagnostic model articulated by Mansell (2005, p. 141) to focus on the role of IU as a facet of the model that is important to address in treatment. Research suggests that individual differences in IU may comp...