The MIDI-CI Profile for MIDI Polyphonic Expression (MPE) specification makes it possible for artists to perform independent gestures for each musical note, with up to three dimensions of expression. With MPE, every note a musician plays can be articulated individually for much greater expressiveness. MPE has broad support from many DAWs, Synthesizers and Controllers.

The specification describes a recommended way of using individual MIDI Channels in MIDI 1.0 and/or MIDI 2.0 to achieve per-note control, enabling richer communication between increasingly expressive MIDI hardware and software.