Abstract: This invention relates to a new and novel device to assist and improve percutaneous vein catheterization of patients. More particularly, this invention relates to a catheterization device which is self-tunneling, has a sleeve for protecting the catheter in the subcutaneous tissue beneath the puncture site, and has an annular skin cup for securing the device to the puncture site. This device allows a catheter to penetrate the skin without the need for a scalpel incision, development of a tunnel, or fluoroscopy, and is self secured to the patient, allowing sutures to be optional. The procedure for insertion of the device can be done in an inpatient or outpatient setting at the bedside by a trained physicians assistant, thereby providing access to the intended blood vessel without the necessity of a surgeon or operating room support.Two embodiments of this new and novel device exist, one being a screw-type device and the other being a moly-type device.