 Kind of Blue is based entirely on modality in contrast to Davis's earlier work with the hard bop style of jazz and its complex chord progression and improvisation. The entire album was composed as a series of modal sketches, in which each performer was given a set of scales that defined the parameters of their improvisation and style. This style was in contrast to more typical means of composing, such as providing musicians with a complete score or, as was more common for improvisational jazz, providing the musicians with a chord progression or series of harmonies.
