Headache is one of the most common presenting complaints to emergency departments. Although the overwhelming majority of these headaches are benign and self-limited, headache can be the initial symptom of life-threatening disorders. It is therefore essential for physicians to have a rational approach to the evaluation of a child or adolescent who presents to the emergency department with headache. The purpose of this article is to review the causes, evaluation, and appropriate investigations for nontraumatic headache in the pediatric emergency department.