Eighteen Norwegian dairy farmers were interviewed to examine their reasons for using homoeopathic treatments in managing their herds' health. Overall, they chose the treatments on the basis of factors related to their personal experience, considerations of individual animals and the framework for dairy production. For individual animals homoeopathy was used as an alternative to conventional veterinary treatment, but at the herd level it was used to complement it. The farmers' use of homoeopathic treatment for personal health problems and the experience of their colleagues with its use in dairy production were important factors motivating their initial use of homoeopathy. Other factors included a desire to decrease the use of antibacterial drugs, reduce costs and find alternatives when conventional veterinary medicine provided no effective treatment. In individual cases, the severity of disease, previous experience and the farmers' personal knowledge and resources were important. These factors parallel those found to influence the use of complementary and alternative therapies in human medicine. The lack of understanding and documentation of the effects of homoeopathic remedies was not important to the farmers, and they valued personal experience more highly than scientific evidence or the opposition to homoeopathy encountered within the veterinary profession.