The Year's Best Science Fiction: Thirteenth Annual Collection of The Year's Best Science Fiction: Thirteenth Annual Collection by Gardner Dozois and Mary Rosenblum and Pat Cadigan and Ursula K. Le Guin and John Kessel and Geoff Ryman and Robert Reed and Michael Flynn and Joe Haldeman and Ian R. MacLeod and William Sanders and Greg Egan and Dan Simmons and Paul McAuley and Allen M. Steele and Maureen F. McHugh and David Marusek and Michael Swanwick and James Patrick Kelly and Poul Anderson and Nancy Kress and Terry Bisson