Multisystemic therapy is an intensive treatment program in psychiatry, generally for young people who engage in chronic violence. It is a combination of family and individual therapy which is individualized for each patient. It generally lasts for four to six months. It is based on the theory that such behavioral problems largely have an environmental cause rather than being rooted in the individual behavior of the young person. However, its effectiveness is controversial - it appears to be no better or no worse than other types of therapy in this situation.