The laboratory at IRCAM is a joint research unit which brings together staff from the CNRS, Sorbonne University, the French Ministry of Culture, and IRCAM. Our work focuses on a vast but clearly identified field: music and organized sound in a unique context where contemporary creation meets scientific and technological research. The laboratory participates in the renewal of musical expression through the contributions of computer science, acoustics, signal processing, cognitive sciences, and musicology. Conversely, specific problems posed by contemporary creation give rise to original scientific advances, be they theoretical, methodological, or practical, the scope of which goes far beyond the musical field.