Type 1 and type 2 diabetes account for up to 90% of all cases of diabetes. However, the remaining “atypical” cases, while rare, appear frequently enough that every practitioner should be aware of them. Some forms of diabetes, distinct from type 1 or type 2 diabetes, are caused by single gene mutations. In addition to monogenic diabetes, other atypical causes of diabetes include: genetic defects in insulin action; diseases of the exocrine pancreas; and endocrinopathies. Atypical Diabetes is divided into three parts, each exploring distinct categories of atypical diabetes, and each part includes case studies that illustrate the clinical challenges presented by different forms of atypical diabetes. This book is a comprehensive resource for the successful diagnosis and treatment of these rare, but significant, forms of diabetes.