Thought suppression is a method frequently employed by individuals who are trying to control their thoughts and behaviors. Although this strategy is known to actually increase unwanted thoughts, it is unclear whether thought suppression also results in behavioral rebound. The study presented in this article investigated the effects of suppressing thoughts of smoking in everyday life on the number of cigarettes subsequently smoked. Study participants recorded their daily cigarette intake and stress levels over a 3-week period. In Week 1 and Week 3, participants monitored intake and stress. During Week 2, in addition to monitoring intake and stress, participants in the experimental groups either suppressed or expressed smoking thoughts, whereas the control group continued monitoring. Our results showed a clear behavioral rebound: The suppression group smoked significantly more in Week 3 than the expression or control group did. Moreover, the tendency to suppress thoughts (measured by the White Bear Suppression Inventory) was positively related to the number of attempts to quit smoking. The implications of our findings for smoking cessation are discussed.