The author first refutes some widely held assumptions regarding medieval timber jointing, and highlights the high degree of sophistication of examples recorded by archaeologists. He examines joints that relied on friction for strength, and which gradually disappeared with the introduction of metal straps and bolts. The structure and uses of the folowing joints are studied: tie-beam lap-dovetail assembly; scarf joint; bridle-joint; mortise-and-tenon joint. The later evolution of this craft is briefly evoked. -- AATA