Anthony John Medeski is an American jazz keyboard player and composer. Medeski is a veteran of New York's 1990s avant-garde jazz scene and is known popularly as a member of Medeski Martin & Wood. He plays the acoustic piano and an eclectic array of keyboards, including the Hammond B3 organ, melodica, mellotron, clavinet, ARP String Ensemble, Wurlitzer electric piano, Moog Voyager Synthesizer, Wurlitzer 7300 Combo Organ, Vox Continental Baroque organ, and Yamaha CS-1 Synthesizer, among others. When playing acoustic piano, Medeski usually plays the Steinway piano and is listed as a Steinway Artist.

Medeski Martin & Wood is an American jazz fusion band formed in 1991, consisting of John Medeski on keyboards, Billy Martin on drums, and Chris Wood on bass. The band is influenced by musical traditions including funk and hip hop and is known for an unconventional style sometimes described as "avant-groove".