J. S. Bach's Fugue in A minor exists in three versions. The version for lute, BWV 1000, is in French lute tablature by Johann Christian Weyrauch. The violin version (in the key G minor) is from Sonata I, BWV 1001, and is in Bach's own handwriting. The organ version, BWV 539, is an unauthenticated and anonymous arrangement in D minor, and has not been used as source material for this transcription. This transcription is primarily based on the version for lute, but a few elements from the violin version are also incorporated. Since the lute version bears traces of some accommodation for technical considerations relating to the idiosyncrasies of the baroque lute, some minor inconsistencies have been resolved by relying on the violin version, since it is in Bach's own hand. About the Book This book contains three complete scores of the fugue. The musical content of each is virtually identical. The solo, duet and trio versions offer three modes for exploring the music. It is recommended that the player learn both the duet and trio versions, mastering each of the parts. In this way, the musical content of all the contrapuntal melodic strands will become deeply embedded in the player's musical imagination. When the player is fully at ease with each of the individual parts of the duet and trio, then the solo version can be mastered with much greater ease. The technical issues, which are at times quite challenging, then are encountered and resolved. A perfectly detailed musical imagination of all the parts then becomes the impetus for full technical mastery.