In a long introduction, Iannis Xenakis presents the composer's situation in the 1980's confronted with computer music. The next four parts detail the musical theories of the French composer through analysis of his Diatope (Centre Georges Pompidou, Paris): macro-composition (sound functions for the creation of structures), micro-composition (the work on sounds), composing with light (Diatope) and UPIC (a brief presentation of his compositional tool). The author demonstrates that artists must be knowledgeable in several disciplines at the same time to profit fully from developing computer music tools and multimedia possibilities.

This article also contains two appendices: a table of correspondence between certain developments in music and mathematics and a mosaic of compositions by Iannis Xenakis