The authors have studied the microvascularization of the intracranial dura mater by microradiographic and histologic examination of 73 injected anatomic specimens. There exists a very abundant superficial arterial plexus which also serves to supply the inner table of the cranial vault. This plexus is continuous, even at the walls of the venous sinuses and the dural septa. The arteries are for the most part tortuous. The veins may be satellites of the arteries or, on the contrary, from a plexiform network passing through crevices in the interior of the dural layer. The walls of these veins consist only of an endothelium to be seen within the fibrous layer of the dura. Often, the arteries compress the venous lumen; this dangerous situation probably explains the frequent occurrence of arteriovenous fistulae of the dura mater, known by the name of dural fistulae.