A new 1.6-mm-diameter (5 French), flexible, plastic disposable ventricular catheter is described. It has a self-attached sealing cap and fits standard Luer terminations of syringes. There are a self-contained stylette, a radiopaque stripe, and a single, smooth, lateral hole drilled through to the lumen. It has been used primarily for selective catheterization of the 3rd ventricle for the injection of contrast media and the collection of ventricular fluid for neurotransmitter analysis during the implantation of deep brain stimulators, but may be used for perfusion, drainage, or connection to pressure transducers.