This is the first book-length study of the Orgelbuchlein, the masterly collection of organ chorales by Johann Sebastian Bach. This 'Little Organ Book' is regarded by Bach scholars as one of the composer's most important achievements and by organ scholars as a milestone in the development of the chorale. In this lucid and absorbing book Russell Stinson, himself an organist, examines the collection from a range of historical and analytical perspectives in a way that will resonate with not only organists and scholars but the average concert-goer or CD-buyer with an interest in the instrument and its music. The book begins with a discussion of Bach's reasons for compiling the collection and his original plans to create a comprehensive set of 164 chorales. Stinson then examines the composer's compositional process in the collection and considers the music in its historical context with attention to each of the three types of chorale: the melody chorale, the ornamental chorale, and the chorale canon. In the next chapters the author looks at each of the forty-six individual compositions, illuminating the structure of each and tracing the evolution through the set of Bach's concept of chorale. The book concludes with a discussion of the Orgelbuchlein's reception from the eighteenth century to the present. The appendix includes a complete score of the chorale 'Ich ruf zu dir' as arranged by C.P.E. Bach and a list of published transcriptions of the chorales for other instruments.