Opioid analgesics are prescribed for moderate to severe pain, particularly of visceral origin. Evidence of efficacy and safety is strongest for use in acute pain and cancer-related pain. They are used in step two and step three of the World Health Organization (WHO) cancer pain ladder. Dependence and tolerance are well-known features with regular use although this should not necessarily inhibit prescribing in palliative care. Some people with chronic non-malignant conditions benefit from analgesic control with opioids, but prescribing should be reviewed regularly.