According to the American Diabetes Association (2011), 25.8 million children and adults have been diagnosed with diabetes in the United States. Approximately 2 million more are diagnosed every year, with another 79 million people considered to be in a pre-diabetes state. These millions of people are at risk of several alterations, including heart disease, stroke, kidney failure, neuropathy, and blindness. Since diabetes has a major impact on the health of millions of people around the world, it is essential for nurses to understand the pathophysiology and associated alterations of this disorder. In this Discussion, you compare two types of diabetes—diabetes mellitus and diabetes insipidus.