This trial is conducted in Europe and the United States of America (USA). The purpose of this study is to test whether insulin detemir is a safe and at least as effective alternative to insulin glargine for the control of blood glucose in basal/bolus therapy in patients with type I diabetes.

Inclusion Criteria:

• Type 1 diabetes for at least 12 months
• Current treatment with basal-bolus insulin regimen for more than or equal to 3 months
• HbA1c less than or equal to 11.0%

Exclusion Criteria:

• Proliferative retinopathy or maculopathy
• Recurrent major hypoglycaemia
• Impaired hepatic or renal function
• Cardiac problems or uncontrolled hypertension