Aim: To evaluate whether management of people with Type 2 diabetes shared between a specialized outpatient clinic and primary health care has noninferior HbA_1c outcomes compared with mono-sectorial management in a specialized outpatient clinic. Methods: A randomized controlled, noninferiority study. People with moderate hyperglycaemia, hypertension and/or incipient complications were eligible for the study. All participants had annual comprehensive check-ups at the outpatient clinic. Quarterly check-ups were conducted by general practitioners (GPs) for the shared care group and by endocrinologists at the outpatient clinic for the control group. The primary outcome was the mean difference in HbA_1c from baseline to 12 months of follow-up. The noninferiority margin for HbA_1c was 4.4 mmol/mol. Results: A total of 140 people were randomized [age 65.0 ± 0.9 years, HbA_1c 52 ± 0.8 mmol/mol (6.9 ± 0.1%), systolic BP 135.6 ± 1.1 mmHg; all mean ± sem]. Peripheral neuropathy was present in 68% of participants and microalbuminuria in 19%; 15% had history of a previous major cardiovascular event. Among study completers (n = 133), HbA_1c increased by 2.3 mmol/mol (0.2%) in the shared care group and by 1.0 mmol/mol (0.1%) in the control group, with a between-group difference of 1.3 mmol/mol [90% confidence interval (CI) −1.3, 3.9] (0.1%, 90% CI −0.1, 0.4). Noninferiority was confirmed in both per protocol and intention to treat analyses. Conclusion: We found that our shared care programme was noninferior to specialized outpatient management in maintaining glycaemic control in this group of people with Type 2 diabetes. Shared care should be considered for the future diabetes management of Type 2 diabetes.