Once-daily dosing with insulin detemir and insulin glargine were compared in a double-blind, randomised, crossover study in type 2 diabetes subjects previously treated with other antihyperglycaemic medications. Blood glucose was measured through continuous glucose monitoring (CGM). Insulin dose was adjusted daily during the titration phase to achieve target blood glucose values of (70-120 mg/dL) during the basal period, defined as 2400-0600 hours. The last meal of the day started at 1800 h and basal insulin was injected at 2000 h. The CGM data for a 24-h period on the second consecutive day after achieving target blood glucose levels were compared between treatments. Twenty-nine subjects completed the study. Over a 24-h measurement period, once-daily dosing with insulin detemir provided glycaemic control very similar to that of once-daily insulin glargine in patients with type 2 diabetes after both had been titrated to the same glucose target. Insulin detemir- and insulin glargine-treated subjects had similar mean 24-h glucose values (133 +/- 21 mg/dL compared with 126+/-20 mg/dL respectively, p = 0.385) and similar glucose values during the basal period (105 +/- 23 mg/dL compared with 98 +/- 19 mg/dL, respectively p = 0.204).Target basal glycaemic control was achieved in all subjects in a mean of 3.8 days for detemir and 3.5 days for glargine (p = 0.360). The mean dose of detemir was similar to that of glargine (26.3 and 26.6 units/day, respectively, p = 0.837). In this study, once-daily dosing of insulin detemir provided 24-h glycaemic control similar to that of insulin glargine in patients with type 2 diabetes.