The high levels of pain and disability associated with undiagnosed migraine or inadequate treatment of migraine offer a potential target for healthcare intervention. Both the individual patient and society are affected by decisions regarding which migraine sufferers are most in need of medical care. Pain is the most important symptom for the individual patient, but disability may be the most important consequence of migraine for an increasingly cost-conscious society. These two perspectives are the components of a migraine severity or impact measure being developed to define migraine sufferers most in need of care. The criteria for developing screening programs provide a context for evaluating healthcare interventions for migraine. Barriers to effective care occur on at least three levels: many people with migraine do not consult doctors; consulters may not receive the correct diagnosis; and even when the correct diagnosis is made, many migraineurs do not receive effective treatment. Screening and impact measures may help both to improve diagnosis and to determine which migraineurs are most in need of care. Public and physician education, screening, and impact measures might circumvent many of the barriers to effective care for people with migraine.