Background: Type 2 diabetes mellitus is a chronic disease that is reaching epidemic proportions worldwide. It is imperative to adopt an integrated strategy, which involves a close collaboration between the patient and a multidisciplinary team of which pharmacists should be integral elements. Objective: This work aims to identify and summarize the main effects of interventions carried out by clinical pharmacists in the management of patients with type 2 diabetes, considering clinical, humanistic and economic outcomes. Methods: PubMed and Cochrane Central Register of Controlled Trials were searched for randomized controlled trials assessing the effectiveness of such interventions compared with usual care that took place in hospitals or outpatient facilities. Results: This review included 39 studies, involving a total of 5,474 participants. Beneficial effects were observed on various clinical outcomes such as glycemia, blood pressure, lipid profile, body mass index and coronary heart disease risk. For the following parameters, the range for the difference in change from baseline to final follow-up between the intervention and control groups was: HbA1c, -0.05% to -2.1%; systolic blood pressure, +3.45 mmHg to -10.6 mmHg; total cholesterol, +10.06 mg/dL to -32.48 mg/dL; body mass index, +0.6 kg/m2 to -1.94 kg/m2; and coronary heart disease risk, -3.0% and -12.0% (among the studies that used Framinghan prediction method). The effect on medication adherence and health-related quality of life was also positive. In the studies that performed an economic evaluation, the interventions proved to be economically viable. Conclusions: These findings support and encourage the integration of clinical pharmacists into multidisciplinary teams, underlining their role in improving the management of type 2 diabetes.