The printed motet collections of Francisco Guerrero provide an invaluable opportunity to study the composer’s habit of revising his music. A large proportion of his motets were published in two or more collections, and comparison of the readings involved reveals a great abundance of reworkings. Although the alterations show considerable variety of approach, they nevertheless disclose much about Guerrero’s priorities and ideals (and changes in these) with regards to, for example, the most effe...