Oral malodor or halitosis is any unpleasant odor emerging from the mouth that is detected by others. Many patients experience extreme discomfort and embarrassment and therefore seek help for this problem. Oral causes, such as poor oral hygiene, periodontal disease, tongue coating, food impaction, unclean dentures, faulty restorations, and dry mouth, are far more common than nonoral causes of malodor. Management may include simple measures such as scaling and root planing, instructions in oral hygiene, tongue cleaning, and mouth rinsing. This paper reviews the current knowledge, etiology, diagnosis, and possible treatment strategies for oral malodor. Emphasis is placed on the recognition of the dental hygienist as a specialist in aspects of patient care and instruction, which relate to the prevention and control of oral malodor.