Since the end of the 13th century and what Bertrand (2015) calls the “watershed” of 1300, the West has witnessed a remarquable diffusion of the knowledge of legal writing. This knowledge seems concentrated in the professional groups of legal clerk, notaries and legal practionners, whose activity is based on this knowledge. The professional group identity is manifested in that period by emerging graphical practices (Andrieux-Reix, 2003). From the middle of the 14th century, knowledge of writing is appropriated by people outside the professional group as attested by an ever larger number of circulating documents, a phenomena that is ill-documented. One such document is the manual of Guillaume Flambard, a noblemen and forest officer of limited status. It brings together documents of various types, and its 170 folios represent a sizable linguistic corpus. The combination of methods (paleographical and discourse analysis) reveal coherent graphical practices in the manuscript, raising the issue of the writer’s place among writing professionals.