Butler maintained a longstanding relationship with the Huntington Library and bequeathed her papers including manuscripts, correspondence, school papers, notebooks, and photographs to the library in her will. The collection, comprising 9062 pieces in 386 boxes, 1 volume, 2 binders and 18 broadsides, was made available to scholars and researchers in 2010.
Butler's work has been associated with the genre of Afrofuturism, a term coined by Mark Dery to describe "speculative fiction that treats African-American themes and addresses African-American concerns in the context of 20th-century technoculture". Some critics, however, have noted that while Butler's protagonists are of African descent, the communities they create are multi-ethnic and, sometimes, multi-species. As De Witt Douglas Kilgore and Ranu Samantrai explain in their 2010 memorial to Butler, while Butler does offer "an afro-centric sensibility at the core of narratives", her "insistence on hybridity beyond the point of discomfort" exceeds the tenets of both black cultural nationalism and of "white-dominated" liberal pluralism.