The techniques of practising the organ described in this book can be useful to both detect as well as modify unconsciously developed habits. These phenomena will be explained and ways of solving difficulties described and demonstrated on extracts of popular organ literature deriving from diverse epochs (138 figures, suggesting ways of practising organ music from J.S. Bach, Mendelssohn, Vierne, Reger, Dupré, Alain…).These practising methods can greatly quicken the process of learning a new piece, activate the hearing and power of conception and thus sensitise the organist for greater detail and creativity.