The Great Fantasia and Fugue in G minor, BWV 542, is an organ prelude and fugue by Johann Sebastian Bach. It acquired that name to distinguish it from the earlier Little Fugue in G minor, which is shorter. This piece is not to be confused with the Prelude and Fugue in A minor, which is also for organ and also sometimes called "the Great".

It was transcribed for piano by Franz Liszt as S.463.

References

• Williams, Peter (2003), The Organ Music of J. S. Bach (2nd ed.), Cambridge University Press, ISBN 0-521-89115-9 
• Yearsley, David (2012), Bach's Feet: The Organ Pedals in European Culture, Cambridge University Press, ISBN 0521199018