This systematic review aims to evaluate the effects of dance (movement) therapy and ballroom dances as therapeutic interventions for adults with physical and mental illnesses in comparison to other interventions or care as usual. A systematic literature search for randomized controlled trials examining dance therapy and ballroom dances published between 1995 and 2011 was carried out in the electronic databases MEDLINE and PsycINFO. 13 publications reporting results from 11 randomized trials (predominantly from USA and Scandinavia) were identified with mostly small samples. They examined breast cancer (n = 2), dementia (n = 1), Parkinson's disease (n = 2), heart failure (n = 1), diabetes type 2 (n = 1), depression (n = 3) and fibromyalgia (n = 1). Dance (movement) therapy had a positive impact for patients with breast cancer, improving quality of life, shoulder range of motion and body image. In patients with depression psychological distress was reduced by dance therapy. Ballroom dances improved balance and coordination in patients with Parkinson's disease and disease-specific quality of life in patients with heart failure. Dance (movement) therapy and ballroom dances seem beneficial for patients with breast cancer, depression, Parkinson's disease, diabetes and heart failure. However, further good quality research is needed to gain more profound insight into the efficacy of these treatment options.