Concerned with genetic engineering, psionic powers, advanced alien beings, and the nature and proper use of power, Octavia E. Butler's science fiction presents these themes in terms of racial and sexual awareness. "Butler consciously explores the impact of race and sex upon future society," Frances Smith Foster explained in Extrapolation. An essayist for the St. James Guide to Young Adult Writers explained that Butler "writes about power, its use and abuse, and how it affects those who wield it. As a science fiction writer, she creates alternate worlds where people are bred for their psionic powers as in the Patternist series or, as in the `Xenogenesis' trilogy, a post-holocaust Earth where survivors must deal with alien visitors who are genetic `traders.' Her situations pit characters against racial, gender, and sexual conflicts and the violence--personal and global--that often results." As one of the few African-American women writers in...