Diabetes mellitus is the most common cause of end stage kidney disease that needs renal replacement therapy (dialysis or kidney transplantation) to sustain life. Certain interventions initiated in the early stage of diabetic kidney disease (DKD), can prevent development or slow the progression to end stage kidney disease. The diagnosis, and the different approaches used in the management of early stage DKD has been highlighted in this book. Various international guidelines and relevant literatures that were published through January 2001 to Jan 2019 for the recommendations on the diagnosis and management of DKD were reviewed. Some controversies in the diagnosis and management of early stage DKD have also been focused. The management of complications of DKD and of advanced DKD is out of scope in this book. This book will be useful for the health care personnel, postgraduate students of internal medicine, and those who are doing diploma/ fellowship in nephrology.