This study constituted the first step in the psychometric development of a self-report screening instrument for risk of opioid medication misuse among chronic pain patients. A 26-item instrument, the Pain Medication Questionnaire (PMQ), was constructed based on suspected behavioral correlates of opioid medication misuse, which heretofore have received limited empirical investigation. The PMQ was administered to 184 patients at an interdisciplinary pain treatment center. Reliability coefficients for the PMQ were found to be of moderate but acceptable strength. Construct and concurrent validity were examined through correlation of PMQ scores to measures of substance abuse, physical and psychological functioning, and physicians' risk assessments. To explore high and low cutoff points for misuse risk, subgroups were formed according to the upper and lower thirds of PMQ scores and compared on validity measures. Higher PMQ scores were associated with history of substance abuse, higher levels of psychosocial distress, and poorer functioning. Future psychometric analyses will consider predictive validity and examine shortened versions of the instrument.