Many people with diabetes are falling short of attaining or maintaining glycemic goals. Self-monitoring of blood glucose (SMBG) is among the many strategies proposed to address the problem. SMBG complements hemoglobin A1c (HbA1c) testing by providing specific information regarding the effects of diet, exercise, and medications on glycemia. Although the importance of self-monitoring is appreciated for insulin-using patients, evidence is still emerging in support of self-monitoring for patients with type 2 diabetes managed with oral agents or diet. Evaluating the available evidence requires a good understanding of the study design and methodology. Although several clinical trials involving SMBG have been insufficiently powered to detect clinically meaningful differences in HbA1c, recent meta-analyses have reproducibly supported the benefit of self-monitoring in non-insulin-treated patients. Although additional work is needed to establish optimal frequency and timing of SMBG, these studies can serve as a basis for conservative recommendations to guide patients and their healthcare providers.