The Year's Best Science Fiction is a series of science fiction anthologies edited by Gardner Dozois. The series, which is unrelated to the similarly titled Year's Best SF series, is published by St. Martin's Press (Griffin).
In the UK the series is entitled The Mammoth Book Of Best New Science Fiction and is published by Robinson. The US edition of the first of the "Mammoth Book" series was The Year's Best Science Fiction: Fourth Annual Collection (1987). The UK series was titled Best New SF 2 through Best New SF 7 from 1988 through 1993.
In 2005 Dozois edited a "Best of the Best" compilation. That compilation and the entire series is to be re-released as e-books in October 2012.