OBJECTIVE: To review the evidence supporting selected complementary and alternative medicine approaches used in the treatment of irritable bowel syndrome (IBS). QUALITY OF EVIDENCE: MEDLINE (from January 1966), EMBASE (from January 1980), and the Cochrane Database of Systematic Reviews were searched until March 2008, combining the terms irritable bowel syndrome or irritable colon with complementary therapies, alternative medicine, acupuncture, fiber, peppermint oil, herbal, traditional, yoga, massage, meditation, mind, relaxation, probiotic, hypnotherapy, psychotherapy, cognitive therapy, or behavior therapy. Results were screened to include only clinical trials, systematic reviews, and meta-analyses. Level I evidence was available for most interventions. MAIN MESSAGE: Soluble fibre improves constipation and global IBS symptoms. Peppermint oil alleviates IBS symptoms, including abdominal pain. Probiotic trials show overall benefit for IBS but there is little evidence supporting the use of any specific strain. Hypnotherapy and cognitive-behavioural therapy are also effective therapeutic options for appropriate patients. Certain herbal formulas are supported by limited evidence, but safety is a potential concern. All interventions are supported by systematic reviews or meta-analyses. CONCLUSION: Several complementary and alternative therapies can be recommended as part of an evidence-based approach to the treatment of IBS; these might provide patients with satisfactory relief and improve the therapeutic alliance.