(Im)politeness is never a depersonalized, decontextualized absolute but always a perception or judgment of appropriate behaviour on a given occasion – what one expects oneself and others to do in a particular social interaction. Nonetheless it is normal for most tabooed words and phrases to be castigated in dictionaries as ‘coarse’, ‘obscene’, ‘insulting’, ‘vulgar’, ‘profane’, ‘taboo’, ‘impolite’ and ‘offensive’, i.e. dysphemistic. The benchmark for such judgements, and more generally for (im)politeness within Anglo communities, is what Allan & Burridge (1991) called the middle class politeness criterion (MCPC). Following a discussion of (im)politeness theories and hypotheses about face management, (cultural) scripts and habitus, the MCPC is closely examined, explained, and tested in the course of examining some texts. The essay concludes with proposals to resolve the apparent limitations of the MCPC.