Crossprogressions

Crossprogressions is a term used in music theory to describe a class of harmonic movements that traverse tonal regions in ways that depart from standard functional harmony. The core idea is to connect chords or keys that are not closely related on the traditional circle of fifths, creating color and contrast rather than predictable cadences. Crossprogressions often employ chromatic mediants, modal mixture, enharmonic reinterpretation, or pivot chords borrowed from parallel keys to bridge distant tonal centers. In practice, crossprogressions appear in jazz, film music, and contemporary pop where composers seek expressive tonal journeys and less predictable resolutions. The effect can be a sense of movement across keys, a change of mode, or a coloristic shift rather than a simple tonic-dominant relationship.

Terminology around crossprogressions is not always consistent, and some analysts may describe similar material using terms such as nonfunctional harmony, chromatic mediant progressions, or common-tone modulations. In some discussions, crossprogressions are contrasted with functional progressions that emphasize clear dominant-to-tonic resolution. Beyond music, the phrase crossprogressions is rarely used in formal mathematics or computer science; when encountered there, it is generally a metaphorical or informal descriptor rather than a standard technical term.

See also: chord progression, chromatic mediant, modal interchange, nonfunctional harmony, common-tone modulation.