Evaluation of the Safety and Effectiveness of the Dexcom Continuous Glucose Monitoring (CGM) System

Inclusion Criteria: * Ages 2 or older * Diagnosis of Type 1 diabetes or Type 2 diabetes * Willing to wear the required number of Systems for the total duration of study wear * Willing to participate in Clinic Session(s) during study wear Exclusion Criteria: * Presence of extensive skin changes/diseases at sensor wear site(s) that preclude wearing the sensor(s) on skin * Known allergy to medical-grade adhesives * Pregnancy * Hematocrit outside specification * ≥ 18 years of age: * Male: 36.0%; * Female: 33.0%; * 13-17 years of age: 35.0%; * 7 years - 12 years of age: 32.0%; * End stage renal disease and currently managed by dialysis or anticipating initiating dialysis during the study wear period * Required or scheduled to have a Magnetic Resonance Imaging (MRI) scan, Computed Tomography (CT) scan, or diathermy during the study wear period