Robert Stalnaker's teaching and research interests are in philosophical logic, the philosophy of mind, and the philosophy of language. He is the author of Inquiry (Bradford Books, 1984), of a series of papers on the logic and semantics of conditionals, most of which are included in an anthology on conditionals, Ifs, edited by W. Harper, G. Pearce, and Stalnaker (Reidel, 1981), and of a number of articles on the semantics and pragmatics of natural language [for example, "Pragmatics," Synthese, 22 (1970) and "Presuppositions," Journal of Philosophical Logic, 2 (1973)]. Papers extending ideas on the problem of intentionality and the relation between language and thought set out in Inquiry include "On What's in the Head," Philosophical Perspectives, 3 (1990) and "Narrow Content" in C. A. Anderson and J. Owens (eds), Propositional Attitudes, (CSLI, 1990). His two volumes of collected papers are: Context and Content (Oxford, 1999), and Ways a World Might Be (Oxford, 2003). Current work in progress concerns the philosophical foundations of "possible worlds" semantics for modal and conditional logics, and uses of this semantic framework to help clarify metaphysical questions about necessity and possibility, concepts of knowledge, common knowledge and mutual belief, inductive reasoning, rational decision-making, and the relation between modality and quantification.