 Diabetes is a disease of glucose metabolism which in the United States in 2007 was estimated to effect at least 17.5 million people with type 2 diabetes mellitus accounting for approximately 90 to 95. Poorly-controlled or treated type 2 diabetes is associated with a variety of health risks, including heart disease, stroke, renal failure, amputations,and blindness and is the seventh leading cause of death in the United States NDIC, National Diabetes Statistics, 2011. A large number of medical treatments are available yet approximately 67 of patients in the United States with type 2 diabetes are unable to reach levels of hemoglobin A1C less than 6.5, which is the target level set by the American Association of Clinical Endocrinologists AACE, State of Diabetes in America, 2011. In patients with type 2 diabetes mellitus who are also morbidly obese, certain bariatric surgical procedures have shown improvement in the control of type 2 diabetes in addition to the expected weight loss effects. However, clinical investigations have pointed to a mechanism other than just weight loss in the improvement of type 2 diabetes in these patients and raised the possibility of utilizing the same mechanism in non-morbidly obese patients. Subsequent basic science research in 2004 involving a surgical bypass procedure of the proximal intestine in non-obese mice with type 2 diabetes mellitus showed remission of diabetes in the majority of mice and marked improvement over medical treatment in the remaining mice 13. Human clinical trials have been conducted in various locations worldwide and have produced similar results to the animal study; a call has been made for studies of new surgical procedures for the treatment of type 2 diabetes in IRB-approved clinical trials 39. In several studies, the duodenal exclusion, which is a procedure which bypasses the duodenum and proximal jejunum and leaves the stomach intact, has been shown to cause remission or marked improvement in type 2 diabetes mellitus without significant weight loss in non-morbidly obese patients. However, no study within the United States has compared the effect of this surgical procedure upon type 2 diabetes with the effect of conventional medical treatment of type 2 diabetes in a controlled clinical trial. In this clinical study, the investigators propose to directly compare the treatment of type 2 diabetes mellitus in non-morbidly obese humans by a surgical bypass of the duodenum and proximal jejunum to the treatment of a similar group of humans treated with conventional medical therapy. Our hypothesis is that a non-bariatric surgical procedure, the laparoscopic duodenal exclusion, will provide improved treatment of type 2 diabetes mellitus in non-morbidly obese patients when compared to conventional medical treatment. The measures of the treatment of type 2 diabetes mellitus in which a difference is expected to be observed are glycosylated hemoglobin A1C HbA1C, fasting glucose, and insulin resistance. The investigators propose a prospective, controlled, non-randomized clinical trial to test this hypothesis. 