The Master of Guillebert de Mets was a prolific, anonymous, illuminator who worked in Flanders during a flourishing period of manuscript production. The Master's name derives from his illuminations in a manuscript of the Decameron, now in Paris, which was signed by the scribe Guillebert de Mets. The Master of Guillebert de Mets was trained in Paris or by Parisian illuminators who worked in Flanders. He lived in or near Ghent toward the end of his life. He illuminated many books of hours and several secular manuscripts, including the works of Roman authors such as Seneca and Valerius Maximus and contemporary authors such as Giovanni Boccaccio and Christine de Pizan.
In his illuminations, the Master created page layouts that closely integrated text, miniature, and border decoration; he also tended to link facing pages thematically and decoratively. Although his miniatures reflect the influence of Parisian International style artists such as the Boucicaut Master, this master's borders often display distinctive broad, heavy leaf forms among which figures cavort. The borders are sometimes so visually arresting that they compete for attention with the main miniatures.