In this paper, the aim is to explore how there can be a role for expression of affect in illocution, drawing upon some ideas about expression put forward by Karl Bühler. In a first part of the paper, I map some active discussions and open questions surrounding phenomena that seem to involve “expression of affect”. Second, I home in on a smaller piece of that larger puzzle; namely, a consideration of how there may be non-conventional expression of affect. I provide (...) some examples of what I take that to involve and set out some premises for approaching it. In a third section, I motivate such an interest by pointing to a question in speech act theory concerning ‘force conventionalism’. This is whether and how illocution can be performed non-conventionally—that is, whether (at least some) utterances can be communicated with illocutionary force without need of convention. I propose that where expression of affect may occur non-conventionally, it may in turn constitute one important route through which at least some kinds of illocution are achieved. In the fourth part of the paper, I sketch an account of such non-conventional expression of affect for the purposes of illocution, by exploring a broadly Bühlerian account of some affects; namely, that some affects are teleological in character, that coordinations may be involved in their satisfactional states, and that uptake of the expressed affect constitutes one subset of such satisfactional states. That exposition points to the contemporary relevance of the “action theory of expression” proposed by Bühler. (shrink)