African-American cultural dance has developed within Black American communities in everyday spaces, rather than in studios, schools or companies. These dances are usually centered on folk and social dance practice, though performance dance often supplies complementary aspects to this. Placing great value on improvisation, these dances are characterized by ongoing change and development. There are a number of notable African-American modern dance companies using African-American cultural dance as an inspiration, amongst these are the Alvin Ailey American Dance Theater, Dance Theatre of Harlem, and Lula Washington Dance Theatre.