Not all conventions use badge numbers. World Horror Conventions typically don't include badge numbers on badges. Although the convention may use them internally, externally it is rare to see them. Most World Fantasy Conventions fall under the same scenario. Since these are professional conventions, as opposed to fan conventions, it is perceived by the boards that the names and locations (city, state/province, country) are more important. There have been past WHCs showing codes for professional designation(s): Author/Writer (Wr), Artist (Ar), Editor (Ed), Publisher (Pu), Agent (Ag), Dealer (Dl), etc. These codes haven't shown up recently as much as in the earlier days of WHC. I've not seen these codes used for WFC recently (2001-2005).