Infantile hemangioma (IH) is the most common vascular tumor of infancy, affecting up to 10% of all infants. Our understanding of IH and its management has greatly evolved. The etiology of IH is unclear but hypoxia is thought to play a key role. Furthermore, GLUT1, IGF2, and HIF-1-? are thought to be important mediators. Current management options include active observation, medical treatment, and surgical intervention. The goals of treatment are preventing cosmetic disfiguration, psychosocial distress, and life-threatening complications. Infantile hemangioma should be managed with an individual, patient-centered approach. Generally, uncomplicated IH can be observed up to 18 months. However, IH should be treated in the setting of bleeding, ulceration, functional compromise, or eventual failure to regress.