This book provides a critical edition of the 'O' manuscript (beginning of the 14th century) of the Roman de Renart. It is supplemented by a varia lectio which takes into account the different readings of the most important 'branches' or short texts of the Roman de Renart. The edition includes an introduction of the work from the perspective of literary studies and philology and explores in detail the main linguistic characteristics of the manuscript. Furthermore, the introduction emphasizes the adaptability within the Renart tradition and documents the creativity of a scribe who added some verses of his own to the text he copied.