The availability of a long-term central venous access for the management of neoplastic and chronic patients is extremely important in order to achieve an easy and safe infusion of chemotherapeutic drugs, blood components, and parenteral nutrition. The authors evaluated 26 adult patients (25 with malignant tumors and 1 with severe asthma) in whom implantable catheter systems were placed subcutaneously between February 1989 and March 1992. Catheters were inserted through the cephalic vein in 13 cases, the subclavia vein in 8 cases and jugular vein in 5 cases. The mean function time was 262 days in deceased patients and 155 in alive ones. There were no infective or thromboembolic complications. The authors, in agreement with the literature, confirm that TIS represent a safe and easy access for a long term i.v. therapy, with a very low complication rate. Furthermore, comfort of the patients is substantially improved and nursing care is greatly facilitated.