The concern that stopping smoking shortly (<8 weeks) before surgery increases postoperative pulmonary complications poses a barrier to tobacco use interventions in surgical patients. We show how this concern arose from a misinterpretation of initial studies and has remained in the medical literature despite the accumulation of later evidence. The persistence of unsubstantiated concepts is not uncommon and can have a significant impact on medical practice. Although it may take several weeks to derive pulmonary benefit from quitting, fear of an increase in pulmonary complications should not be a barrier for clinicians to help their patients quit smoking at any time before surgery.