The “Treatise on Musical Objects” by Pierre Schaeffer is regarded as his most important work on music and its relationship with technology. Schaeffer refers to his earlier research in musique concrète and expands this to suggest a methodology of working with sounds resulting from the recording process. Drawing on acoustics, physics, and physiology, but also philosophy and the relationship between subject and object, Schaeffer’s book summarizes his theoretical and practical work in music composition. North and Dack present an important book in the history of ideas in Europe that will resonate far beyond electroacoustic music.