Anorectal manometry is used in the treatment of complex anorectal disorders, such as fecal incontinence and intractable constipation. In a 3-year period at one institution 308 anorectal manometries were performed. A total of 168 procedures were performed for complaints of fecal incontinence, 77 for constipation, and the remainder for a variety of anorectal disorders. Anorectal manometry in those under 20 years of age was performed most often to differentiate Hirschsprung disease from functional constipation, as well as to provide a differential diagnosis related to congenital anorectal anomalies. In patients between the ages of 21 and 40 years, evaluation of fecal incontinence (especially obstetrical injuries) was most significant. Fecal incontinence accounted for twice the number of anorectal manometries for those between the ages of 41 and 60. For those over 60 years of age, the majority of anorectal manometries were done for fecal incontinence rather than for constipation (nearly a 4:1 ratio). Anorectal manometry is a valuable physiologic adjunct in the evaluation, diagnosis, and treatment of organic and functional disorders of the anorectum.