This thesis examines how relational issues of law in economic integration are being approached in Africa. At its core, relational issues deal with the legal interactions among community, national, regional and international legal systems within the context of economic integration. The theory is that effective economic integration is the product of properly structuring and managing – within well-defined legal frameworks – vertical, horizontal and vertico-horizontal relations among states, legal systems, laws and institutions. Put differently, an economic community must have well-structured and managed relations between itself and other legal systems as a necessary condition for its effectiveness. After expounding this theory and applying it to the state of affairs in Africa (focusing principally on four regional economic communities), the original contribution of the thesis to knowledge on economic integration in Africa can be captured in a few words: Africa’s economic integration processes have not paid systematic or rigorous attention to relational issues. The interactions between community and member states’ legal systems, among the various communities, as well as among member states’ legal systems, have neither been carefully thought through nor placed on a solid legal framework. Where attempts have been made to provide a legal framework, it has been incomplete, unsatisfactory, and, sometimes, grounded on questionable assumptions. The thesis argues that, unless these shortfalls are remedied, the progress and effectiveness of Africa’s economic integration will be seriously undermined. The thesis reveals that even if all the infrastructural, socio-economic and political challenges that bedevil Africa’s economic integration were to disappear, - and it is these challenges that most of the scholarship on Africa’s economic integration are devoted to - there remains so much in the realm of law which, if unaddressed, will hinder its success and effectiveness