The dimensionality and correlates of the Intolerance of Uncertainty Scale (IUS) were examined in a sample of 239 university students. In addition to completing the IUS, participants completed measures of worrying, anxious arousal, anhedonic depression, the big five personality dimensions, and the Need for Closure Scale. A factor analysis of the IUS suggested that it includes the following dimensions: (a) desire for predictability; (b) tendency to become paralyzed in the face of uncertainty; (c) tendency to experience distress in the face of uncertainty; and (d) inflexible uncertainty beliefs. Subscale scores computed on the basis of the factor analysis were differentially associated with the other variables.