David G. Hartwell began his annual series of SF anthologies for two reasons: to establish such a series in mass market paperback (there had not been one since Wollheim's series ended in 1990), and to focus exclusively on science fiction, in contrast to "other books" (presumably meaning by Dozois) which had "blurred the boundaries between science fiction and everything else." His stories, Hartwell said, were clearly science fiction "and not something else." Also in contrast to Dozois' books, these had a preference for shorter stories rather than longer.

HarperCollins adopted the Eos imprint created originally by Avon, then abandoned it after 2010. Hartwell created a companion fantasy annual in 2001. Co-editor Kathryn Cramer joined both series in 2004. (Though her name did not appear on the covers for her first two years of both series.) The fantasy series moved to small press publisher Tachyon in trade paperback with volume 6, then to Tor.com for its final volume. The final SF volume, edited by Hartwell alone, appeared in hardcover from Tor.

Most reprinted authors: Gene Wolfe (19), Michael Swanwick (18), Robert Reed (140, Gregory Benford (13), then Stephen Baxter, Terry Bisson, and Nancy Kress (11 each).

Most frequent sources: F&SF (87), Asimov's (86), Interzone (33), Realms of Fantasy (22), Nature (21).