This issue of Endocrinology and Metabolism Clinics, guest edited by Dr. Sethu K. Reddy, is devoted to Diabetes. Articles in this issue include: Approach to Multicultural Issues in Diabetes; Clinical Utility of Genetic Testing in T2DM; Utility of CGM - Type 1 and Type 2 Diabetes Mellitus; Islet Cell Transplantation; Use of Telemedicine; Nonalcoholic Steatohepatitis; Microbiome: Role in Type 1 and Type 2 Diabetes Mellitus; Population Management and Diabetes; Pre-diabetes; Metformin: What do we know?; Insulin: Making Sense of Current Options; Nutrition in Diabetes; Bariatric Surgery: Pathophysiology and Outcomes; Future Therapies in Diabetes; Lipodystrophic Syndromes; and In-patient Diabetes Management in the 21st Century.