The use of chronic opioid therapy for the treatment of chronic pain has increased dramatically in recent years. With the increase in the use of opioids, there has been a concomitant rise in prescription opioid misuse and abuse. Clinical practice guidelines for the treatment of chronic pain recommend screening for prescription opioid misuse with urine drug testing (UDT) for all patients prior to initiating opioid therapy and regularly during treatment. If patients have aberrant UDT results appropriate follow-up should ensue. However, less than 25% of patients who are prescribed chronic opioid therapy receive UDT and no empirical data are available about how providers alter clinical treatment following an aberrant UDT. The proposed research study will employ mixed research methods to study UDTs and methods for managing patients who abuse prescription opioids. The specific aims of this proposal are: (1) in a national sample of patients, estimate the incidence of UDT and identify variables associated with the use of UDT, (2) conduct qualitative interviews with clinicians to explore perceptions of barriers to UDT and methods for managing patients with aberrant UDT results, and (3) describe current clinical practice following an aberrant UDT result. These results will inform the development of a larger implementation study designed to increase the use of UDTs and assist providers in managing patients who have aberrant UDT results. The long-term goal of this research is to ensure the safe use and reduce preventable harm from prescription opioid medications.