Background: Evaluation of the anorectal function, clinically, structurally, and functionally, in patients with faecal incontinence should ensure appropriate and individual treatment. Methods: Two hundred and twenty-six patients with faecal incontinence were reviewed regarding disease history and results of anorectal physiological tests and anal ultrasonography. Results: The mean age was 54 years, and 191 patients (85%) were female. Sixty-two patients had passive faecal incontinence only, 49 had urge faecal incontinence only, and 115 had both passive and urge faecal incontinence. Patients with passive faecal incontinence only had a significantly higher voluntary contraction pressure and less external sphincter abnormalities than patients with urge faecal incontinence or both passive and urge faecal incontinence. The structural abnormalities of the internal and external anal sphincters identified on anal ultrasonography were significantly associated with a low maximum resting pressure and with a low voluntary contraction pressure, respectively. The causes identified for this faecal incontinence were: in 90 patients idiopathic, in 76 obstetric injury, in 36 internal anal sphincter degeneration, in 20 anal surgical injury, in 6 rectal prolapse, and in 9 patients miscellaneous. Conclusions: The anal sphincter structure as demonstrated by ultrasonography was closely related to the anorectal function, as determined by anorectal physiological tests, and the observations from these were reflected in the range of patient-reported symptoms. Anal ultrasonography and anorectal physiological tests are useful tools, enabling us to identify the mechanisms and causes of faecal incontinence in at least 60% of the patients.