Infantile hemangiomas (IHs) are the most common benign vascular tumors of childhood. IH of "segmental" morphology, are clusters of hemangiomas with a configuration involving a broad anatomic territory of skin. They are the least common of all types and generally larger than regular hemangiomas, morphologically characterized as plaque-like lesions. Head and neck segmental hemangiomas have a higher risk of causing life-threatening complications and of having associated structural anomalies, i.e., PHACES syndrome (Posterior fossa malformations, hemangiomas, arterial anomalies, coartation of the aorta and other cardiac defects, eye abnormalities and sternal clefting or supra abdominal raphe). We present a patient with a segmental IH over the right anterior neck complicated by ulceration and life threatening arterial bleeding. Although segmental hemangiomas of head and neck have high incidence of ulceration, fortunately life threatening bleeding events are rare with only 7 previously recorded cases. We recommend that large, neck IH be followed closely for evidence of ulceration and that MRI/MRA be performed to adequately assess their vascular supply. Direct extension of the ulceration into arterial vessels is a possibility and can lead to severe bleeding. Life-threatening bleeding is an unusual complication of IH and may represents a surgical emergency. In such cases we recommend a multidisciplinary approach to their treatment.