What is Planing?

Planing (also called parallel harmony or parallel chord motion) is a harmonic technique in which a chord shape is moved up or down in parallel motion, maintaining the same interval structure between the notes. Instead of following traditional harmonic rules, the entire chord moves together as a block.

For example, a composer might take a major chord and shift the entire chord shape upward step by step, keeping the same spacing between the notes. Each chord moves in the same direction with the same internal intervals, creating a smooth, sliding harmonic effect.

Planing became especially common in Impressionist music, particularly in the works of Claude Debussy and Maurice Ravel. It is also used in jazz and film music to create atmospheric textures and colorful harmonic movement. Because the chords move together in parallel, the effect often sounds fluid and dreamlike rather than strongly tied to traditional tonal harmony.