The disciplines of general philosophy, philosophy of language, and linguistics have in common an interest in saying what it is that we can infer: what meaning, what truth; and how those inferences are to be justified. The papers collected in this special issue all contribute further to these continuing discussions. They exhibit a wide range of approaches and starting points, and, taken together, we believe that this collection provides a stimulating overview of some key current concerns in the fields of argumentation, linguistics, and philosophy of language, in particular the role of inferring in both reasoning and understanding.