The accurate assessment of acute and chronic pain is challenging. Assessment should be approached by taking a relevant history, examining the patient and ordering suitable investigations if necessary. Pain scales facilitate the initial assessment of the patient and provide a measurement of the success or otherwise of pain-relieving interventions. A comprehensive pain history should investigate both the pain (site, character, context and treatment history) and the patient (including psychosocial yellow and red flag markers of life-threatening pathology, anxiety and depression). The aims of examination and investigation are to document baseline signs and look for potential underlying causes of the pain. Investigations can include blood tests, anatomical investigations or functional investigations.