The Jazz Sessions spotlights Andrew Hill, a great and even groundbreaking composer and pianist. While many of his contemporaries were totally jettisoning the rhythmic and harmonic techniques of bop and hard bop, Hill worked to extend their possibilities; his was a revolution from within. He exhibited a determined command of his materials, however abstract they might sometimes be. His composed melodies were labyrinthine, rhythmically and harmonically complex tunes that exhibit a sophistication born of mastery, not chance or contingency. As a pianist, Hill had a flowing melodicism and an elastic sense of time. Like his composing, Hill's playing had an ever-present air of spontaneity and was almost completely devoid of cliché.