The texts self-published by such late 17th-century French performer-composers as Chambonnières, Marais and Gaultier are, by definition, ‘authoritative’. Their authority, however, is quite different from that of authoritative sources in later repertories, repertories in which musical works are stable entities defined in detail by texts serving as instructions that performers are expected to follow literally. These self-publishing composers were first and foremost performers who composed largely for themselves and their intimates, and each composition married musical conception and personal performing style in ways that do not obtain when a composer composes for a wider public. Self-publication was the means by which these performer-composers sought to control the texts in which their compositions circulated. The detailed texts found in their publications were neither prescriptive (instructions to be followed literally), nor descriptive (transcriptions of particular performances), but exemplary, representations of sample performances in the composers’ personal styles that purchasers of their publications could emulate. This is the significance of their authority.