Vascular ultrasound plays an important role in the visual depiction of arteries, veins, and changes of tissue in lymphatic diseases. In the case of arteries, this ranges from endothelial dysfunction over measuring the increase of intima media thickness to the detection of stenoses, occlusion, or aneurysm. Ultrasound helps to differentiate in functional arterial diseases such as primary and secondary Raynaud's syndrome as well as arterial compression syndromes like entrapment syndrome of different arterial regions or the chronic exceptional compartment syndrome of the lower leg. Ultrasound plays a central role in the diagnosis of rare arterial diseases like large vessel vasculitis, arterial dissection, cystic adventitial degeneration, and the differentiation of vascular malformation especially in children, thus, permitting ultrasound-guided intervention and follow-up controls. In venous thrombosis, sonography is the primary imaging method, while follow-up controls help in the prediction of recurrent venous thrombosis. Ultrasound is a tool to determine the cause and severity of chronic venous insufficiency and allows different therapeutic procedures for the treatment of varicose veins to be visually monitored.