In the light of the most recent non-invasive and invasive diagnostic findings, E. Malan's classification of 1974 is reproposed. This introduces the concept of prevalence to Malan-Puglianisi's previous classification of 1964. A common denominator is proposed for all vascular malformations, not only those involving the extremities, to simplify this pathology still further: the presence or otherwise of the diversion phenomenon.