In this essay, originally published in 1985, Carl Dahlhaus addresses the problem of how to integrate timbre into our understanding of music while honoring its resistance to description and quantification. In particular, he explores the history of orchestration in terms of an opposition between “coloristic” and “structural instrumentation,” the latter defined as that which “actively intervenes in the compositional logic [Tonsatz] of the music, rather than being merely dependent on it.” Dahlhaus’ essay is grounded squarely in the common-practice era: his compositional points of reference span from Haydn to Richard Strauss, and he is particularly concerned with how instrumentation can reveal structural patterns that stand athwart the formal trajectories suggested by tonal analyses.