Several of our most useful drugs cannot be administered orally. This paper is a summary of our work with a new drug delivery system: a totally implantable, continuous infusion pump, with a self-contained inexhaustible power source. Currently, after bench tests and animal experimentation, we have initiated clinical series utilizing this device to treat individuals with refractory thromboembolic conditions by intravenous heparin, and patients with localized solid tumors by intra-arterial chemotherapy. The use of this device for the infusion of insulin in the management of diabetes mellitus is yet in the laboratory stage of development. In addition to improving dy-today diabetic control and obviating the need for daily insulin injections, this pump offers an ideal opportunity to test whether optimal blood glucose control can significantly prevent or delay the onset of the crippling vascular complications of diabetes. The potential uses of this device, in many fields, are myriad.