The verbal categories of tense and aspect have been studied traditionally from the point of view of their reference to the timing and time-perspective of the speaker's reported experience. They are universal categories both in terms of the semantic-functional domain they cover as well as in terms of their syntactic and morphological realization. Nevertheless, their treatment in contemporary linguistics is often restricted and narrow based, often involving mere recapitulatoin of traditional semantic and morphotactic studies. The present volume arises out of a symposium held at UCLA in May 1979, in which a group of linguists gathered to re-open the subject of tense-and-aspect from a variety of perspectives, including — in addition to the traditional semantics — also discourse-pragmatics, psycholinguistics, child language, Creolization and diachronic change. The languages discussed in this volume include Russian, Turkish, English, Indonesian, Ameslan, Eskimo, various Creoles, Mandari, Hebrew, Bantu and others. The emphasis throughout is not only on the description of language-specific tense-aspect phenomenon, but more on the search for universal categories and principles which underlie the cross-language variety of tense and aspect. In particular, many of the participants address themselves to the relationship between propositional-semantics and discourse-pragmatics, in so far as these two functional domains interact within tense-aspect systems.