An understanding of the anatomic, physiologic, and pathophysiologic aspects of cough is necessary to appropriately diagnose and treat patients with cough. In the majority of persons, cough that is acute and self-limiting is usually secondary to a viral upper respiratory tract infection; cough that is chronic and persistent is usually due to chronic bronchitis or postnasal drip. In the remaining persons, to determine the cause of cough, it is necessary to systematically consider anatomic locations were receptors and afferent nervous pathways are located. Definitive treatment of cough depends on determining its precise cause and then initiating specific therapy for the underlying disorder. Only when the cause of cough remains unknown or when cough performs no useful function and its complications represent a potential hazard to the patient, should symptomatic treatment be considered. Combination cough preparations should not be prescribed.