Book 4 welcomes contributions by Martin Cuellar (a lyrical etude), David Karp (a Halloween piece), and Kevin Costley (an arrangement of America the Beautiful), along with showpieces by Melody Bober and Kevin Olson. The repertoire also features a classical theme solo of Offenbach's Barcarolle, and an equal-part duet. New elements include: sixteenth note patterns, compound meters, inversions of I, IV, and V chords, octave scale passages, some LH melodic passages, and more intricate accompaniments. The CD and teaching pages address more advanced performance issues.