Internal carotid artery disease is a challenge to the optometrist because of its full spectrum of manifestations. A detailed case history and a thorough evaluation of the ocular and visual signs and symptoms are invaluable in the appropriate management of the patient. The optometric practitioner must consider this disease in middle-aged or elderly patients who present with suggestive signs and/or symptoms. Appropriate diagnosis and management of the disease will, it is hoped, result in the continued visual health and longevity of these patients.