Background: Brief procedures that reduce smoking behaviour may be useful in reaching the many people that do not seek help for smoking addiction.Objectives: The current study aimed to determine if one component of Acceptance and Commitment Therapy (ACT), cognitive defusion, could be useful in reducing smoking behaviour in a sample of students.Methods: The study employed a between-subjects three-arm design. For one week, participants were asked to reduce their cigarette consumption. To aid them in their reduction, participants were randomly allocated to one of three conditions: the first received a defusion procedure, the second received an experiential avoidance procedure and a control condition received no procedure. For a second week, the instruction to reduce cigarette consumption was lifted. During both weeks participants were required to monitor their smoking behaviour via a tally diary system.Results: The defusion condition smoked significantly less than the control condition during week one and significantly less than the control and experiential avoidance conditions during week two.Conclusion: Results are discussed in terms of the potential utility of defusion in this domain, and the limitations of this preliminary research that would need to be addressed in future investigations.