In this article, I explore the functional varieties of language, i.e. registers (or genres), used in different school subjects and university disciplines, examining the ranges of registers used in a selection of subjects and disciplines — their registerial profiles. I draw on Giovanni Parodi’s research into registerial profiles of university disciplines and on systemic functional work on registerial profiles of school subjects, showing how they complement one another. I sketch an outline of a comprehensive view informed by these pioneering contributions so that future research can fill in gaps and further illuminate registerial profiles of different fields of study, curricular composition and sequence of registers and learner paths through institutions of education seen in terms of expanding personal registerial repertoires. For the sake of conceptual clarification, I also touch on different approaches to the phenomenon of functional variation within language according contexts of use under the headings of ‘register’ and ‘genre.