The purpose of this study is to gather a mixed racial group of relatively healthy male Veterans (for example, White, African-American, and Hispanic), who are at least 50 years of age. These men will be followed to see what types of diseases they develop and to determine if racial differences in lifestyle, blood test results, or genes are related to the types of diseases that are found. Diseases of particular interest are prostate cancer, other cancers, cardiovascular disease (for example, heart attacks and stroke), high blood pressure and diabetes. The group to be followed will consist of about 16,000 men recruited from about 40 VA Medical Centers across the country. Each man will be followed for at least five years depending on when he enters the study.