The National Museum of African American History and Culture Council (the museum's board of trustees) sponsored a competition in 2008 to design a building with three stories below-ground and five stories above-ground. The building was limited to the site chosen by the site selection committee, had to be LEED Gold certified, and had to meet stringent federal security standards. The cost of construction was limited to $500 million ($ in dollars). The competition criteria specified that the winning design had to respect the history and views of the Washington Monument as well as demonstrate an understanding of the African-American experience. The winning design was required to reflect optimism, spirituality, and joy, but also acknowledge and incorporate "the dark corners" of the African-American experience. The museum design was required to function as a museum, but also be able to host cultural events of various kinds. Hundreds of architects and firms were invited to participate in the design competition. Six firms were chosen as finalists: