ABSTRACT This paper discusses the principal findings of a new integrated dataset of transnational armed conflict in Africa. Existing Africa conflict datasets have systematically under-represented the extent of cross-border state support to belligerent parties in internal armed conflicts as well as the number of incidents of covert cross-border armed intervention and incidents of using armed force to threaten a neighbouring state. Based on the method of ‘redescribing’ datapoints in existing datasets, notably the Uppsala Conflict Data Project, the Transnational Conflict in Africa (TCA) data include numerous missing incidents of transnational armed conflict and reclassify many more. The data indicate that (i) trans-nationality is a major feature of armed conflict in Africa, (ii) most so-called ‘civil wars’ are internationalised and (iii) the dominant definitions of ‘interstate conflict’ and ‘civil war’ are too narrow to capture the particularities of Africa’s wars. While conventional interstate war remains rare, interstate rivalry using military means is common. The dataset opens up a research agenda for studying the drivers, patterns and instruments of African interstate rivalries. These findings have important implications for conflict prevention, management and resolution policies.