Music therapy is a science that has been applied since many centuries ago, but it has been organized as a profession during the past century. This science studies the therapeutic effects of music in human beings. Profesionals who practice this science are called "music therapists" and they must be trained not only in music theory and performance, but also in psychology, anatomy, research techniques, and other subjects. Today, we can find music therapy research in many areas such as the effects of music in children with autism, adults with psychiatric illnesses, elderly with Alzheimer and Parkinson disease, people with brain injuries, among others. Numerous studies demonstrate the functionality of music therapy in patients with neurological disorders. These studies show that music helps patients to gain control over their walking patterns after a brain injury, stimulates long and short term memory in patients with Alzheimer disease, and increase self esteem and social interaction in elders (Rev Méd Chile 2001; 129: 219-23).