In the ED, correct diagnosis is the necessary foundation on which specific therapy is based. There is no substitute for obtaining a thorough history and examining the patient competently. Patients with a past history of primary headaches, such as migraine, also may be afflicted with (new) secondary headaches. Although efficiency is desirable from the perspective of ED management, a thoughtful approach complemented by the judicious selection of tests is compatible with that goal as well as achieving the desired outcome of accurate diagnosis and relief of pain. Arrangements for long-term follow-up are important.