This book explores the thesis that in the Kwa languages of West Africa, aspect and modality are more central to the grammar of the verb than tense. Where tense marking has emerged it is invariably in the expression of the future, and therefore concerned with the impending actualization or potentiality of an event, hence with modality, rather than the purely temporal sequencing associated with tense. The primary grammatical contrasts are perfective versus imperfective. The main languages discussed are Akan, Dangme, Ewe, Ga and Tuwuli while Nzema-Ahanta, Likpe and Eastern Gbe are also mentioned. Knowledge about these languages has deepened considerably during the past decade or so and ideas about their structure have changed. The volume therefore presents novel analyses of grammatical forms like the so-called S-Aux-O-V-Other or "future" constructions, and provides empirical data for theorizing about aspect and modality. It should be of considerable interest to Africanist linguists, typologists, and creolists interested in substrate issues.