The document summarizes the economic base of Cape Cod and the surrounding islands. It states that more than half of the region's economic base depends on tourism, retirees, and second home owners. While Cape Cod has diversified more, the economies of Martha's Vineyard and Nantucket remain highly dependent on tourism and are therefore more volatile. The top industries supporting the region's economy are tourists and seasonal residents, retirees, business services, and commuters.