Placement of large-bore central venous catheters via a jugular or subclavian vein is becoming increasingly common. Although the great majority of these catheters are successfully placed by clinicians using anatomic landmark techniques, this procedure is neither innocuous nor always successful. Serious complications, including hematomas, arterial injury, and pneumothorax can occur. The patient may experience considerable discomfort when multiple needle passes are made. Sonographic imaging of the jugular and subclavian veins can significantly improve the safety, speed, and comfort of the procedure by defining the vascular anatomy of the jugular and subclavian veins before puncture, showing complications from prior attempts or placements of central venous catheters in these vessels, and providing guidance for needle puncture of the jugular and subclavian veins.