Study objectives: To analyze variation in beliefs that potentially motivate thoracic surgeons in the design of posttreatment surveillance strategies for lung cancer patients and to examine the relationship between motivation and follow-up intensity, Design: International survey. Setting: Ambulatory care. Participants: All 3,700 members of the Society of Thoracic Surgeons were surveyed to measure their follow-up practices during the 5-year period after treatment, physician beliefs, and variation in these beliefs. The relationship between beliefs, as potentially motivating factors, and follow-up intensity was also analyzed. Measurements and results: Age, General Thoracic Surgery Club membership, percentage of practice that was noncardiac, South Central United States practice location, and overseas practice location were most frequently related to beliefs that potentially motivate physicians in the design of surveillance strategies. When viewed independently of follow-up practice patterns, thoracic surgeons appear to be motivated by the desire to please patients, avoid malpractice suits, and improve patient quality of life. When viewed in relation to self-reported follow-up, none of these motivating factors were consistently associated with follow-up intensity. Belief in curative treatment of recurrence and enhanced Likelihood of immediate palliative treatment leading to improved survival were the factors most frequently associated with variation in follow-up. Although the ability of the logistic and stepwise regression models to predict test use and follow-up intensity was less than optimal for TNM I stage I patients, predictive ability was substantially improved for TNM stage II and III patients by including earlier-stage practice patterns as an independent variable. Conclusions: Physician characteristics and beliefs predicted a less than expected amount of the variation in self-reported follow-up intensity by TNM stage when modelled without knowledge of follow-up practice for any other TNM stage, Discrepancies between self-reported and actual follow-up may be partially responsible, although lack of surveillance guidelines is more likely. The inclusion of barriers to follow-up may improve future models.