Diagnosis of vascular malformations is essentially clinical, based on the evolution and morphology of lesions. A biopsy is rarely needed to evaluate the nature of the vessels. Imaging examinations are necessary to assess the extension of malformations as well as the osteomuscular and visceral compromise. New techniques such as 3D angio-CT scan and angio-MRI improve the diagnosis of some vascular malformations, especially the large combined ones such as Klippel-Trénaunay syndrome, thus limiting the need for invasive procedures. On the other hand, the advances in laser technology, particularly pulsed dye laser for port-wine stains and Nd:YAG laser for superficial venous malformations constitute new alternatives for the management of these patients. Other emergent treatments include microfoam sclerotherapy for venous and combined, slow-flow malformations, and new embolizing materials associated to surgery for arteriovenous malformations. The second part of this review is focused on the complementary diagnosis (imaging exams, pathology and accessory tests) and multidisciplinary and specific treatment based on the different groups.