‘Authority’ examines the narratives of legitimation entrenched in popular attitudes towards dictionaries. They are often constructed as gatekeepers, selectively admitting words because they have been judged worthy of being recorded. In contrast, the changing wordlists of descriptive dictionaries simply reflect the diction of current use. The underlying premises are quantitative (based on the frequency and prevalence of particular forms) rather than qualitative (based on evaluations of ‘good’ or ‘bad’, legitimate or otherwise). The real measure of authority for a dictionary resides in being authoritative — a quality which rests firmly on the careful and systematic assessment of usage.