Jack Dann and Gardner Dozois have jointly edited a series of themed science fiction and fantasy anthologies, mostly published by Ace Books (a few were issued by other publishers). Because most of the earlier volumes had one-word titles followed by an exclamation mark, it has also been known as "The Exclamatory series."
The series began in 1980 with Aliens!, issued by Pocket Books. Ace took over publication with Unicorns!, the second volume, in 1982. Under Ace, most volumes of the series were originally themed around a certain type of "magic" entities, with science fiction-oriented volumes being the exception. Hence, it was known as the "Magic Tales Anthology Series" until 1995. The "magic" guideline was abandoned in 1996 when the series switched its focus to more strictly science fiction themes, beginning with Hackers. Volumes have usually appeared at the rate of one or two per year, with 38 volumes as of 2007.
The stories selected for the books tend to be reprints of previously published stories, some of them decades old. Each book has a preface by the editors, along with a short introduction for each of the stories, focused on other works by the story's author.
Jack Dann and Gardner Dozois have also co-edited anthologies that are not part of this series, such as Future Power (1976).