Although Miles Davis first appeared on bebop recordings of Charlie Parker, his first important session as a leader was called The Birth Of The Cool. An album containing all the recordings of this group is available. The cool jazz style has been described as a reaction against the fast tempos and the complex melodic, harmonic, and rhythmic ideas of bebop. These ideas were picked up by many west coast musicians, and this style is thus also called West Coast jazz. This music is generally more relaxed than bebop. Other musicians in the cool style include saxophonists Stan Getz and Gerry Mulligan, and trumpet player Chet Baker. Stan Getz is also credited with the popularization of Brazilian styles such as the bossa nova and samba. These and a few other Latin American styles are sometimes collectively known as Latin jazz.

Many groups in the cool style do not use a piano, and instead rely on counterpoint and harmonization among the horns, usually saxophone and trumpet, to outline chord progressions. Pianist-led groups that developed from this school include those of Dave Brubeck (with Paul Desmond on saxophone), Lennie Tristano (with Lee Konitz and Warne Marsh on saxophones), and the Modern Jazz Quartet or MJQ (featuring John Lewis on piano and Milt Jackson on vibraphone), which also infuses elements of classical music. The incorporation of classical music into jazz is often called the third stream.