Objective The purpose of this study was to evaluate the use of a new long-acting basal insulin, insulin glargine (IG), in children with type 1 diabetes. Study design Data from 114 subjects, age 2 to 18 years (mean, 12.2 years; 54 boys, 60, girls), were collected for 9 months before and 9 months after IG treatment. During IG therapy, all subjects received morning neutral protamine Hagedorn insulin (given with insulin lispro; Humalog) to provide daytime insulin coverage. The numbers of nonsevere and severe hypoglycemic events, hemoglobin Ale values body weight, and daily insulin dose were recorded at each clinic visit. Results The mean (+/-1 SEM) frequency of nonsevere hypoglycemie events per week decreased from 2.0 +/- 0.1 to 1.3 +/- 0.1 (P < .001). Severe hypoglycemic episodes were reduced from a total of 22 in the 9 months before IG to nine in the 9 months after IG. Severe nocturnal events were similarly reduced from 14 to four episodes. The mean (+/-1 SEM,) hemoglobin Ale levels were 9.6 +/- 0.1% (baseline), 9.4 +/- 0.16% at 3 months (P = .18),9.3 +/- 0.1% at 6 months (P = .03), and 9.3 +/- 0.1% at 9 months (P = .01). Conclusion insulin glargine therapy can reduce hypoglycemic episodes in children and adolescents with suboptimal glucose control without jeopardizing glycemic control.