Kidney disease in diabetes (diabetic nephropathy) tends to run in families. It is likely, therefore, that there are genes that predict or are associated with either getting or not getting diabetic nephropathy. The GoKinD Study will provide clinical information and DNA for investigators to look for these genes. Evaluation will be performed and DNA obtained from approximately 1100 diabetic persons with kidney disease and 1000 diabetic persons without kidney disease. In some cases, samples for DNA will also be obtained from the parents of these subjects. Clinical information and DNA will be coded so that individuals cannot be identified, but the DNA can be linked to the clinical data from the individual. Multiple investigators will be able to use this genetic material to test hypotheses about the genetics of kidney disease in diabetes.