This Companion is the first accessible guide to Bartok's music and is an ideal introduction to the composer for students, performers and concert-goers. Part I of the book sets out the cultural, social and political background in Hungary at the beginning of the twentieth century, and considers Bartok's interest in and research into folk music. Part II surveys his compositional output in all genres, relating changes in style to broad aesthetic issues, his folk music studies, and his activities as a pianist, music editor and teacher. The final part reveals the wide variety of responses to Bartok's music in Europe and the United States, both during and after his lifetime. It includes a comparison of analytical approaches to his music and an evaluation of performances including those of the composer himself. The book is written by a team of specialists, who represent the latest thinking on the composer and his music.