This article argues against the current strict liability approach of the cartel offence by presenting a case for the introduction of a mens rea of cartel crime. The cartel offence is presented as a serious and normatively stigmatic crime which requires a mens rea if fair criminalisation is to occur. A mens rea of intention is presented as the ideal candidate and the applicability of intention is explored. The issue of omission in the cartel context is also addressed and this in turn leads to a call for the creation of a new offence of failing to report cartel activity to the competition authority.