Kaiser successfully built a highly diversified construction business consisting of 82 companies. His company handled millions of dollars of highway and bridge construction as well as several dams (e.g. Hoover Dam), levees and pipelines in the United States, Canada and Cuba. Kaiser also established the first integrated steel mill on the West Coast and a major aluminum company. His most enduring achievements were the employee health plan and 19 hospitals he established, which were the first health maintenance organizations in the United States.