Book 4 is filled with tuneful and challenging etudes that are sure to please while focusing on specific concepts such as melody voicing in chords, tone production, phrase shaping with disjunct melody, chord leaps, arpeggios, trills, melody shared between the hands, chromatic scales, parallel motion scales, shaping melody in a complex texture, octave tremelos and so on. Composers featured are J. C. Bach, Burgmüller, Gurlitt, Reinhold, Gasparini, Rebikov, Czerny, Streabbog, Schumann, Duvernoy and more.