The femoral vein is a convenient venous access site which has remained relatively neglected since earlier reports of major complications. However, over the last 10 years, its beneficial use for various purposes (mainly haemodialysis) justifies a reexamination of the value of femoral venous catheterization. The ease of femoral catheterization and its complications were prospectively studied in 92 intensive care patients. Of the 113 attempts made by physicians, 75% of whom were inexperienced, 103 (91.2%) were successful. Insertion resulted in 17 (15%) arterial punctures and 5 local hematomas. Seventy catheters were left in place for an average of 8.8 days. No clinical manifestations of thrombosis were observed. Bilateral phlebography was carried out before removal of the catheter in 70 cases; 45 (64%) of these controls were normal. Of the remaining 25 pathological phlebograms, there were 11 (15.7%) fibrin sleeves, 2 (2.8%) partial thromboses of the common femoral vein which could be directly linked to the venous cannulation, and various abnormalities not directly due to the catheterization (superficial femoral vein thrombosis (4), thrombosis of calf or popliteal veins (18]. One case of catheter septicaemia occurred. Microorganisms were present in 15 (18.3%) of 82 catheter cultured tips. Percutaneous catheterization of the femoral vein might therefore be considered as a good venous access route. It can be successfully used by inexperienced physicians. There is no serious risk of injury to surrounding structures and the risks of thrombosis and infection are acceptable in comparison with other routes.