Fecal incontinence is an under-reported complication of scleroderma. Ten incontinent patients with scleroderma were evaluated through anorectal manometry and compared with 20 incontinent patients without scleroderma who were matched for age and sex as controls. The scleroderma patients had a higher voluntary external anal squeeze pressure, whereas the resting internal anal sphincter pressure was similar to that of the control group. The threshold for rectal sensation in the scleroderma group was significantly less than that in controls. Episodes of fecal incontinence, anal canal length, and maximal tolerable volume were not significantly different between the study groups. The rectoanal inhibitory response was abnormal in 80% of patients with systemic sclerosis but was normal in 70% of the controls. Stool consistency was significantly looser in the scleroderma patients. Treatment of fecal incontinence in scleroderma patients may be successful in many patients using a combination of dietary and pharmacologic manipulation because diarrhea is an important etiologic cofactor superimposed on reduced internal anal sphincter pressure.