Lukas Ligeti's (b. 1965) Notebook is several things: an album and an ensemble, but also a creative practice and an ongoing series of pieces, all situated in the liminal space "somewhere between composition and improvisation." As a creative practice, Notebook is Ligeti's evolving methodology for creating conditions in which structure and spontaneity blur and overlap, manifesting his musical voice while also giving players a great deal of expressive agency, as musicians who are willing and able to "think aloud."

The members of Notebook - the band - are all musicians who thrive in the spaces in between, that is, who are fluent enough to move seamlessly between notated complexity and focused improvisation, and, as the occasions call for, to draw on and morph between several idioms, often within the span of a single piece.

All four pieces on Notebook (the album) emerged from a multi-faceted process that, as the case may be, might begin with a handwritten score, which might include a combination of precisely notated pitches and rhythms, melodies without rhythms, rhythms without melodies, descriptions of processes, delineations of parameters, cues, things to do, and things not to do. But it might instead begin with verbal instructions, and/or a sonic object to be responded to. Over time Ligeti might mix-and-match these methods of transmission, or reshape the material altogether, the aim always being to best situate players to make conscious musical decisions while still realising an extremely clear artistic vision. The result is music that feels both rigorously shaped and disarmingly spontaneous. The music of Notebook fully inhabits the composition/improvisation continuum: While some moments are clearly composed and others clearly improvised, there are many gradations - "an infinite amount of right" - in between.