It is learned that Giles' nickname in his youth was Ripper. At one point, a prequel spin-off named "Ripper", detailing adventures of young Giles, was proposed.
Writer Carl Ellsworth was fired by Joss Whedon immediately after completing the script. Although Ellsworth said he was shaken-up by the firing, he admitted "It just wasn't a fit".
Willow's line, "Wild on me equals spaz" was cut when shown on the BBC because, in the UK, "spaz" is a mildly offensive term, deriving from the archaic term "spastic", used to describe a handicapped or disabled person.
Xander's soldier experience and military knowledge is referenced several times in the series, most notably in Innocence (1998) and Graduation Day: Part 2 (1999).
Angel was supposed to look bored when Cordelia attempts to flirt with him, but David Boreanaz kept laughing, and they decided to add it in.