Numerous French treatises over several centuries have pointed to the use of fauxbourdon as a common and important method for the elaboration of liturgical chant. Although the term fauxbourdon has been closely identified with musical practices and compositions dating from the time of Du Fay, it continued to be used to describe a method of performing liturgical chant in France well into the twentieth century. During the seventeenth and eighteenth centuries in particular, fauxbourdon was frequently referred to in treatises and accounts of chant performance, but the term itself was rarely described in any satisfying detail, making it difficult to know what the practice was actually like, and how it related to—or differed from—what we know about fauxbourdon’s earliest forms. Fortunately, a number of printed and manuscript sources from the late sixteenth to the eighteenth century—including dictionaries, treatises, ceremonials, and collections of music—include examples of composed fauxbourdon settings. An examination of these reveals both general and specific information about the practice that on occasion conflicts with contemporary definitions and descriptions, but also reveals a certain range of variation in what was included within the purview of the term.