The purpose of this study is to determine whether Type 1 diabetic patients using the Guardian RT glucose sensor can improve glycemic control over a 12-week period, compared to patients using self-monitoring blood glucose testing (SMBG) alone.

The long-term benefit of tight glycemic control in diabetics is well documented. HbA1c generally assesses the average/long term quality of glycemic control. On a daily basis, patients assess their glycemic control through finger stick measurements (SMBG), which allows them to adjust their therapy. A device which would provide a patient with a real-time glucose value, as well as high and low alerts, could aid the patient in knowing when to perform confirmatory SMBG tests and intervene so that dangerous glycemic excursions may occur less frequently.

Inclusion Criteria:

• Type 1 Diabetes for at least 12 months
• HbA1c must be 8.1% or above at study entry
• Intensive Insulin Therapy 3 months prior to study entry

Exclusion Criteria:

• Impaired hearing or vision (must see screens and hear alarms)
• Unable to comply with protocol
• Chronic debilitating or psychiatric disturbances