This paper presents some key findings of studies of actionality and the verbal grammar–lexicon interface in two Nguni Bantu languages of South Africa, Xhosa and Southern Ndebele. We describe interactions between grammatical tense marking (and other sentential bounding elements) and lexical verb types, arguing for the salience of inchoative verbs, which lexically encode a resultant state, and, in particular, a sub-class of inchoative verbs, biphasal verbs, which encode both a resultant state and the “coming-to-be” phase leading up to that state. We further discuss other important features of actional classes in Xhosa and Southern Ndebele, including topics such as the role of participant structure and the relative importance of cross-linguistically prominent distinctions such as that between Vendlerian activities and accomplishments. Although differences between Xhosa and Southern Ndebele are evident both in the behaviour of individual tense-aspect forms and in the interpretive possibilities of specific verbs, the general patterns are quite similar. This similarity suggests that the patterns are likely to extend to other Nguni languages, as well, and that cross-linguistic comparison of particular lexical items across these languages are both feasible and likely to bear fruit.