The increasing importance of music as a therapeutic benefit in mental hospitals has prompted this study. Numerous unscientific reports and papers concerned with music therapy have been published; however, material based upon controlled experiments and results is available which has proven valuable in the study of this growing aid for mental patients. The reference material in the following chapters has been organized and limited to objective reports produced by those who have devoted their interest and time to the facts about the use of music as a therapeutic agent in mental hospitals.