This guide to Monteverdi's music is constructed in three sequences. The first is a catalogue of Monteverdi's works, both surviving and lost, in as near as possible date order, followed by a list of undated manuscript sources. In the case of sources containing more than one work, the contents of the volume are listed in the order in which they appear in the earliest, or the only, source (this order is not always followed in later and modern editions – see Chapter 3, above). The second sequence is a catalogue, by short title only, of prints and manuscripts containing contrafacta of Monteverdi's music: that is, adaptations of his settings by a different author to texts that are usually sacred or spiritual in character (the first lines of these settings are given in the Index). The third sequence is an index of first lines and titles, which serves as an index both to the catalogue and to the discussion of individual works in the text of this book. Each work can be traced in the catalogue from the index through an identifier, which includes the date of publication or first performance, or the year(s) in which a work, now lost, is discussed in Monteverdi's letters or another source; manuscripts are identified by the sigla for the library in which they are located. Dates or library sigla followed by [CF] refer to contrafacta. Dates followed by a superscript number follow the convention found in RISM (Répertoire international des sources musicales, the International Inventory of Music Sources), specifically in the volume Recueils imprimés XVIe-XVIIe siècles (Munich-Duisburg, 1960).