Title: Medtronic CEP304 Outcomes Study. Description: The Medtronic CEP304 Outcomes Study is designed to evaluate the safety and effectiveness of the Hybrid Closed Loop system (HCL) in adult and pediatric patients with type 1 diabetes in the home setting. This device system consists of an insulin pump, a new generation of Medtronic glucose sensor, a new insertion device for the sensor, and a new glucose meter. The system is designed to translate sensor information and direct the pump to provide the needed dosage of insulin automatically and continuously. The study is divided into a run-in and study period (about 8 months long), as well as a continuation period (about 6 months long). During the run-in period, the patient will wear a sensor for two weeks and then will be randomized (assigned to a study group by an automatic system) to either get the HCL system or continue with their current therapy. During the continuation period, all patients will use the HCL system. To understand the safety and effectiveness of the HCL system, study participants will need to return for study visits and telephone calls for about 1 year from the first visit. All data collected during this study will be used to support the safety and effectiveness of the HCL system in adult and pediatric patients.