In this paper the relationship between six functions of language and values is analysed and applied to managers in the Australian public service. A hierarchy of language and values is developed and the language of expression, signalling, description, advice, command and argument is related to values which managers (and employees) invoke to define and condition the work relationship. Following Karl Popper, the importance of argument is emphasised as a vehicle for growth and development. The results of a study of communication styles of public sector senior and middle managers show that argument is used less frequently than all other functions of language (except for middle managers' use of the commanding function). Senior managers rely more on the language of command and less on the language of description and advice than do middle managers.