Combining antihyperglycemic agents with complementary mechanisms of action is a cornerstone of type 2 diabetes mellitus (T2DM) management. Although several fixed-dose combinations (FDCs) are available, representing standard types of combination therapy in T2DM, use of these products has been limited.; To address the likely concerns of prescribers and patients regarding the use of FDCs in the treatment of T2DM, literature searches were performed to ascertain the bioavailability, efficacy, tolerability, and cost-effectiveness of the currently approved FDCs compared with their individual component drugs given as separate pills in combination. Additionally, data were collected on rates of adherence, clinical outcomes, and overall treatment costs with FDCs versus dual therapy with the same constituent drugs.; Bioavailability is equivalent for FDCs and dual therapy used in T2DM. Efficacy and tolerability also appear to be at least as good with FDCs as with dual therapy. Retrospective analyses have suggested that FDCs can enhance adherence to therapy, presumably as a result of the reduction in pill burden, and improved adherence may result in improved glycemic control and reduced disease management costs. In addition, because currently available FDCs come in two or more dose-strength formulations, they also afford some measure of dosing flexibility.; The available evidence supports the wider use of FDCs in the treatment of patients with T2DM.