As a traditional health care system, yoga combines physical activity, breathing techniques and meditation. It is increasingly used as a preventive or therapeutic means. Yoga has been researched in hundreds of randomized controlled trials. Positive effects are especially found for chronic pain conditions, hypertension, depression and in supportive cancer care. While there are case reports of serious adverse events associated with yoga, the risk seems to be extremely low and comparable to other forms of physical activity. Yoga can thus be considered as a safe and effective adjunct therapy for a number of conditions.