This article reviews the natural history of type 2 diabetes and emphasizes that the disease is a continuum from impaired glucose tolerance and impaired fasting glucose to frank diabetes. Understanding this natural history aids the clinician in identifying those individuals most at risk for developing type 2 diabetes. Early intervention may significantly limit the severity of the microvascular and macrovascular complications of diabetes. Additionally, this article discusses oral antidiabetic agents and reviews their potential effectiveness at the different stages in the continuum to aid the clinician in developing a treatment strategy.