This review aimed to critically evaluate the literature on the efficacy of biofeedback for functional anorectal disorders, rate these biofeedback applications according to established guidelines, and make recommendations for this field based on the literature. The Medline and PsychInfo databases were searched to obtain all papers published from 1975 to 2003 that included the terms "biofeedback" and either "constipation" "pelvic floor dyssynergia" "fecal incontinence" or "anorectal pain." Adult and pediatric papers in any language were screened. Prospective studies with five or more participants and a description of the treatment protocol and outcome were selected for review. Seventy-four studies qualified for review: 33 trials on fecal incontinence (FI), 38 on pelvic floor dyssynergia (PFD) or functional constipation, and 3 on anorectal pain. Only 20% of studies were controlled outcome trials. Treatment protocols, etiological subgroups studied and outcome measures varied greatly. The overall average probability of successful treatment outcome for patients treated with biofeedback was 67.2% for functional FI and 62.4% for constipation. There were insufficient data to warrant such calculation for anorectal pain. According to standard efficacy rating criteria, biofeedback treatment is efficacious for functional constipation or PFD in children and probably efficacious in adults; probably efficacious for functional FI; and possibly efficacious for anorectal pain. Utilizing data from all applicable studies, we found that success rate per subject is significantly higher for biofeedback treatment than for standard medical care for PFD/functional constipation, and FI (p < .001 for both). Biofeedback treatment may therefore be viewed as a valuable adjunct to medical management of functional PFD/constipation and incontinence. A number of recommendations for future investigations are made based on the review.