Colorectal cancer (CRC) is the second leading cause of cancer in Puerto Rico (PR) accounting for approximately 1,500 individuals annually, which represent 12% of all cancer cases in the island. The genetic epidemiology of CRC among Hispanic populations is not well studied, hence studies focused on large, well defined ethnic groups such as Puerto Ricans, are clearly warranted. The first step towards evaluating the molecular, environmental, and genetic epidemiology of CRC in PR is to establish a population-based familial CRC registry. The following specific aims have been proposed: