The character design was created by Paul Dini and Bruce Timm from her appearances in the animated series Batman: The Animated Series. Harley is clad in the manner of a traditional harlequin jester. She is one of the rare characters to have originated in an animated series and thereafter been added to the comic book continuity, as opposed to the other way around. She is also the only such character to have gone on to have an ongoing eponymous comic book.