The mission of the Department of Energy (DOE) is to advance the national, economic, and energy security of the United States.

The DOE promotes America's energy security by encouraging the development of reliable, clean, and affordable energy. It administers federal funding for scientific research to further the goal of discovery and innovation — ensuring American economic competitiveness and improving the quality of life for Americans.

The DOE is also tasked with ensuring America's nuclear security, and with protecting the environment by providing a responsible resolution to the legacy of nuclear weapons production.

The United States Secretary of Energy oversees a budget of approximately $23 billion and more than 100,000 federal and contract employees.