Opioid analgesics are powerful pain relievers, but inappropriate use can cause a variety of problems. Especially, in chronic non-cancer pain, inappropriate use of opioid analgesics might fail to improve or even worsen the quality of life and activities of daily living of patients impaired by pain. The Japan Society of Pain Clinicians has developed the Guidelines for Prescribing Opioid Analgesics for Chronic Non-cancer Pain (Third Edition), which answers basic clinical questions concerning opioid management as summary statements in accordance with the most recent scientific evidence and expert opinion. The guidelines emphasize patient selection (e.g., obvious organic cause of the persistent pain, low risk of psychosocial factors, pain refractory to non-opioid therapies, and good adherence to medication). Furthermore, patients should be treated with an oral dose of 90 morphine milligram equivalents/day as the upper limit and target duration of 3-6 months. For pain in cancer survivors that is not directly caused by cancer, such as pain after treatment or pain associated with complications or pre-existing conditions, these guidelines should be followed.