Gagging is a protective reflex to stop unwanted entry into the mouth and oropharynx. Some people have a reduced or absent reflex, while others have a pronounced one. Pronounced gag reflexes can compromise all aspects of dentistry, from the diagnostic procedures of examination and radiography to any form of active treatment. In some patients with marked gagging reflexes, it can lead to avoidance of treatment. Many techniques have been described that attempt to overcome this problem, and a variety of management strategies is necessary to aid the delivery of dental care. This is a review of the etiology of gagging problems, clinical assessment, and their classification and categorization prior to clinical treatment. It discusses as well methods for managing patients with gag reflexes during dental treatment.