In this study, David Willgren attempts to provide answers to two fundamental questions in relation to the formation of the `Book' of Psalms: "how?" and "why?". The first relates to the diachronic growth of the collection (how are these processes to be reconstructed, and on what grounds?), while the second relates to questions of purpose (to what end are psalms being juxtaposed in a collection?).By conceptualizing the `Book' of Psalms as an anthology, and by inquiring into its poetics by means of paratextuality, David Willgren provides a fresh reconstruction of the formation of the `Book' of Psalms and concludes, in contrast to the canonical approach, that it does not primarily provide a literary context for individual psalms. Rather, it preserves a dynamic selection of psalms that is best seen not as a book of psalms, but as a canon of psalms.