Percutaneous infraclavicular cannulation of the subclavian vein in even the tiniest infants can be performed with safety and ease using a plastic cannula metal needle stylet and following plastic catheter. This route for achieving superior vena caval catheterization provides a most satisfactory method for central pressure monitoring, long term antibiotic administration, total parenteral nutrition, and exchange transfusion. Few serious complications have been noted in over a hundred infant cannulations. The procedure can be performed in the intensive care nursery with a success rate of over 95%. Sepsis rates in clean cases are acceptably low. Most sepsis is due to other clearly identifiable sources of infection in these already critically ill infants.