In the heart of the new millennium, worlds beyond our imagination have opened up, blurring the line between life and art. Embracing the challenges and possibilities of cyber space, genetics, the universe, and beyond, the world of science fiction has become a porthole into the realities of tomorrow. In The Years Best Science Fiction Twenty Third Annual Collection our very best SF authors explore ideas of a new world. This venerable collection brings together award-winning authors and masters of the field such as Bruce Sterling, Alastair Reynolds, Ian McDonald and Stephen Baxter. And with an extensive recommended reading guide and a summation of the year in science fiction, this annual compilation has become the definitive must-read anthology for all science fiction fans and readers interested in breaking into the genre.