The perforating veins, as the name suggests, are the veins that perforate the muscular aponeuroses ensuring communication between the superficial and the deep veins. Located at the bend of the elbow, almost constantly, there is a vein, named perforating vein of the elbow, which is of great interest to the nephrologist who is responsible for the management of vascular access for hemodialysis (HD). It represents, in fact, because of its intrinsic characteristics and topographical reasons, a valuable resource for the creation of a vascular access for HD, especially in obese patients, elderly patients, diabetics, and patients affected by peripheral vasculopathy. Arterio-venous fistulae (AVF) constructed with the perforating vein of the elbow are relatively easy to perform, have an excellent patency rate, a low incidence of early thrombosis, adequate flows, and a low incidence of the steal syndrome. In other types of AVFs, the perforating vein of the elbow subtracts flow to the superficial veins slowing or preventing their full maturation, and can become a problem in measuring the blood flow of the AVF. But still, its presence can maintain patent a fistula in case of poor compliance of the superficial veins, while awaiting for interventional procedures able to accelerate a subsequent maturation. This review intends to explore the role that the perforating vein of the elbow plays in the physiology and pathology of the AVF, in relation to the issues that most frequently occur in clinical practice.