The goals of the proposal are the development and commercialization of a long-term implantable infrared glucose sensor for insulin dependent diabetics. The sensor will provide quasi-continuous measurement of blood glucose levels and an alarm indicating pending hypo- or hyper- glycemia. The sensor will measure the near infrared absorption spectra across a blood vessel or vascular membrane at a multitude of discrete wavelengths (up to 18 wavelengths) and computing the glucose concentration using the absorption spectra based on an algorithm. The measurement will be taken once every 20 minutes unless specially programmed or when in an alarm situation. In these cases the measurement will be taken every 5 minutes. The initial project is aimed to design and build a breadboard glucose sensor unit and to demonstrate its ability to measure blood glucose in vivo in two dogs for a period of 3 months. Four sensor heads will be implanted in each dog including sensor heads for: vein, arterial, interstitial and vascular membrane. In the next phase of the study, the investigator will design and build the miniaturized implantable long term (5 years) glucose sensor for implantation in human. These sensors will be tested in dogs for one year and in people on acute basis.