ABSTRACT We conducted several tests of the idea that an inclination toward thought suppression is associated with obsessive thinking and emotional reactivity. Initially, we developed a self-report measure of thought suppression through successive factor-analytic procedures and found that it exhibited acceptable internal consistency and temporal stability. This measure, the White Bear Suppression Inventory (WBSI), was found to correlate with measures of obsessional thinking and depressive and anxious affect, to predict signs of clinical obsession among individuals prone toward obsessional thinking, to predict depression among individuals motivated to dislike negative thoughts, and to predict failure of electrodermal responses to habituate among people having emotional thoughts. The WBSI was inversely correlated with repression as assessed by the Repression-Sensitization Scale, and so taps a trait that is quite unlike repression as traditionally conceived.