OBJECTIVE: The vast majority of patients undergoing colonoscopy in the United States are given sedation. There are a number of potential advantages to performing colonoscopy without sedation. We sought to determine the attitude of patients toward unsedated colonoscopy in our three practice settings (a university medical center, a cancer center, and a Veterans Affairs medical center), and to see if there were factors that predicted willingness to try it. METHODS: Four-hundred thirty-four adult patients undergoing outpatient colonoscopy completed questionnaires before and after their procedures providing demographic information and assessing willingness to undergo colonoscopy without sedation. Patients were routinely given meperidine and midazolam for their procedures unless they specifically requested that they be unsedated (10 patients). RESULTS: Only 16.9% of our patients were willing to undergo colonoscopy on their preprocedure questionnaire. Willingness increased modestly on the postprocedure questionnaire to 22.6% (p = 0.01). Logistic regression analysis disclosed that male gender, having a college degree, low anxiety based on preprocedure anxiety scales, and lower doses of sedative drags used during colonoscopy were the best predictors of willingness to undergo colonoscopy without sedation in the future. CONCLUSIONS: Only about a fifth of patients undergoing colonoscopy in our three practice settings expressed a willingness to try colonoscopy unsedated. Male gender, higher levels of education, and low anxiety scores on simple scales of preprocedure anxiety may help to predict willingness. Efforts to substantially increase the frequency of patients willing to undergo colonoscopy without sedation will likely require increased patient counseling and education.