Most chronic headache syndromes can be identified by conducting a careful interview that yields a thorough understanding of the patient's headache experience. The interview should explore the PQRST of the pain: provocation, quality, region, strength and time course, with the last element being the most helpful. Associated symptoms, such as nausea and vomiting in migraine, can be clues to the etiology. A list of all current medicines and the frequency of use should be obtained, since overuse of various analgesics can convert paroxysmal migraine into chronic daily headache. Psychosocial issues should be addressed, since depression can manifest as chronic headache. Changes in mood, energy, appetite, sleep, libido, enjoyments and suicidal ideation (represented by the acronym MEASLES) can indicate depression. A neurologic examination is important, and any focal findings warrant tomographic imaging of the brain. Findings on physical examination, however, are usually normal in patients with chronic headache. Laboratory and imaging studies are of most value when targeted to elucidate potential diagnoses raised by the detailed interview.