The management of type 2 diabetes mellitus (T2DM) by primary care physicians (PCPs) has become increasingly complex due to limitations on consultation time, an increasing array of drug treatment options, and issues of comorbidities and polypharmacy. Diabetes is a progressive condition and treatment with a single glucose-lowering agent can only address limited pathophysiologic targets and does not provide adequate glycemic control in many cases. Consequently, most patients with T2DM will eventually require treatment with multiple glucoselowering medications. Oral combination therapy in T2DM may be given as multiple-pills, or as single-pill, fixed-dose combinations (FDCs), the latter of which offer convenience, ease of administration, and a reduction in the medication burden. Therefore, FDCs can potentially improve patients' treatment adherence and optimize achievement and maintenance of glycemic targets. However, cost factors also need to be considered. An understanding of the issues associated with the use of combination therapy in T2DM will help PCPs to guide patient-centered decision making and promote the effective management of T2DM.