The Namur Hours, presented here, introduces an important addition to the oeuvre of the Provencal painter Enguerrand Quarton. Given the limited number of miniatures attributable to Quarton, this manuscript, containing two splendid folios by his hand, provides a unique opportunity to reassess his work as an illuminator. The manuscript also reflects collaboration with four other miniaturists, of whom three are Provencal artists known from outside work. The authors propose to identify the best of these hands, responsible for most of the illuminated programme, with Pierre Villatte, a close colleague of Quarton. The two artists collaborated on the Cadard Altarpiece (Chantilly, musée Condé) and Villatte continued working in the artistic tradition of his celebrated associate well into the 1480s. In a broader perspective, the stylistic and codicological analysis of this book sheds new light on Avignon-based manuscript production and brings into question the traditional “workshop” model. In contrast, this study highlights the existence of close collaboration between independent artists.