Dizziness comes in many forms in each age group - some specific to an age group (e.g. benign paroxysmal vertigo of childhood) while others span the age spectrum (e.g., migraine-associated vertigo). This content organizes evaluation and management of the dizzy patient by age to bring a fresh perspective to seeing these often difficult patients. The pediatric section begins with a review of vestibular embryology and physiology and moves toward a comprehensive discussion of methods - both bedside and in the vestibular lab - to evaluate the child with dizziness, or "clumsiness," concluding with an exploration of the differential diagnosis of dizziness and relevant findings. Dizziness in the adolescent points to migraine headache as a common cause, enumerates treatment strategies for migraine-associated vertigo, and offers guidelines for when to image the adolescent with dizziness. Adult dizziness is more a compilation of the relevant diagnoses, but the section starts with dizziness that can affect young adults - especially members of our Armed Forces fighting overseas - traumatic brain injury/blast injury. This content also has relevance for patients in motor vehicle accidents and head injury patients. Medicolegal aspects of evaluation and management of dizzy patients are succinctly covered in "Evaluation of Dizziness in the Litigating Patient." The final chapter in this section, "Other Causes of Dizziness," provides a very thorough overview of unusual causes of dizziness in the adult population. Dizziness associated with advancing age is quite common and often multifactorial, as is highlighted in the chapter "Dizziness in the Elderly." A comprehensive review of the posterior cerebral circulation, transient ischemic attacks, and posterior circulation stroke is presented in the chapter, "Vertebrobasilar Insufficiency." No coverage of dizziness in the elderly is complete without an exposition of polypharmacy and medication effects. Other common diagnoses of dizziness in the elderly are thoughtfully reviewed along with a survey of new and old techniques to rehabilitate the older patient with dizziness or disequilibrium. Patients presenting with dizziness can harbor serious, if not life-threatening, conditions such as stroke, brain abscess, or severe chronic ear disease. At the end of several articles, the reader will find a relevant table - What Not To Miss - a list of clinically significant signs and symptoms not to ignore, or conditions (differential diagnosis) that may masquerade as that discussed in the chapter but critically important that the practitioner should not overlook in the evaluation of the patient. Many articles in this edition start with a clinical scenario so the reader can recognize common presenting symptoms, demographic features, and factors in the medical history that will aid in making the diagnosis.