ObjectiveSurgery rates for lumbar spinal stenosis (LSS) have increased despite inherent risks, high reoperation rates, and a lack of evidence for benefit over conservative treatment. Scant research has investigated how people make decisions about treatment, which may help clinicians better support patients during the course of care. The purpose of the present study was to explore the beliefs of people with LSS and how they make decisions about treatment. DesignCross-sectional qualitative study. MethodsSemi-structured individual interviews were conducted with participants who had LSS (based on diagnostic imaging and recent symptoms). Transcribed interview data was analyzed using directed content analysis informed by the Health Belief Model. ResultsTwelve patients (mean age 75.3 years, range 63–87 years, 9 female, 6 with previous LSS surgery) participated. The Health Belief Model appeared useful for explaining decisions about treatment. Perceived threat of LSS was higher in those who had surgery. Patients who decided on surgery perceived themselves as more susceptible to surgery, often because of pathoanatomical beliefs. These patients had lower perceived control over symptoms and the treatment decision itself. Although patients saw benefit in conservative treatment because of its lower risk and ability to foster self-management, many had no or poor education and reported previous experiences with ineffective conservative treatment. ConclusionPatients with LSS make decisions about treatment by weighing the perceived threat of LSS against the perceived barriers and benefits of conservative treatment. Consistent and nonthreatening educational messages from clinicians may help these patients during their decision-making process.