Patients with type 1 diabetes trained in multiple daily insulin injection were treated with two diffferent kinds of long acting insulin preparations. The two insulin preparations were glargine and ultralente insulin. Patients were randomized to receive one of the two insulin preparations for the first 4 months followed by the second preparation for a further four months. Short acting insulin used was the same during both periods. We found that glargine insulin was better than ultralente insulin in our study.