What is a Functional Harmony?

Functional harmony is a system of understanding how chords relate to each other and move within a key to create musical structure and direction. In this system, each chord has a specific function or role that helps establish tension, movement, and resolution in a chord progression.

The three main harmonic functions are tonic, dominant, and subdominant. The tonic chord acts as the point of rest or stability in a key. The dominant chord creates tension that strongly leads back to the tonic. The subdominant chord often prepares the movement toward the dominant. These relationships create the sense of motion that listeners perceive as harmonic progression.

Functional harmony is most commonly associated with Western classical music and tonal music from the Baroque, Classical, and Romantic periods. It also forms the foundation for many styles of popular music, where chord progressions rely on predictable patterns of tension and resolution within a key.