Irritable bowel syndrome (IBS) is a common, chronic disorder that leads to decreased health-related quality of life and work productivity. A previous version of this review was not able to draw firm conclusions about the effectiveness of homeopathic treatment for IBS and recommended that further high quality RCTs were conducted to explore the clinical and cost effectiveness of homeopathic treatment for IBS. Two types of homeopathic treatment were evaluated in this systematic review: 1. Clinical homeopathy where a specific remedy is prescribed for a specific condition; 2. Individualised homeopathic treatment, where a homeopathic remedy based on a person's individual symptoms is prescribed after a detailed consultation.