In this paper I revisit some of the basic premises of applied linguistics research, with particular reference to the emergent field of professional discourse studies. Beginning with an overall orientation towards different paradigms of applied research, I outline the main facets of an applied linguistic mentality as a basis for developing what I call an ‘Applied Linguistics of Professions’. I then go on to offer an overview of the communicative turn in medical education and practice in the UK. I draw upon my own work in recent years in a number of healthcare sites to engage with some of the challenges facing applied linguists in an interdisciplinarily crowded space, in terms of both analytic practice and uptake of research output. With regard to the conditions of analytic practice, I focus on how categorisation and interpretation are central to all professional activity, to the extent that within applied linguistics and discourse studies, these are both the object of study and the process through which we study the professional habitus. With regard to the consequences of our research, I offer a set of observations that can be seen as a way of opening a dialogue among communication researchers and professional practitioners around issues of ‘discovery/usefulness’ and discriminatory expertise’, if our research is to attain practical relevance.