Traditionally, the selection of vascular access and the eligibility for native arteriovenous fistula construction was mainly determined by findings of clinical examination. However, in addition to a complete history and physical examination, National Kidney Foundation/Dialysis Outcome Quality Initiative (NFK/DOQI) recommended that routine pre-operative color Doppler ultrasonographic vascular mapping should be performed in all hemodialysis patients who are candidates for access formation. This concerns the routine implementation of a non-invasive, safe and cost-effective method that permits the identification of vessels that are suitable for arteriovenous fistula (AVF) construction, acknowledging that supporting Level I evidence is still lacking. Indeed, available data supporting the significance of mapping on access maturation and patency rates are limited and conflicting.