This paper examines the history of regional integration in Africa, what has motivated it, the different initiatives that African governments have pursued, the nature of the integration process, and the current challenges. Regional integration is seen as a rational response to the difficulties faced by a continent with many small national markets and landlocked countries. As a result, African governments have concluded a very large number of regional integration arrangements, several of which have significant membership overlap. While characterized by ambitious targets, they have a dismally poor implementation record. Part of the problem may lie in the paradigm of linear market integration, marked by stepwise integration of goods, labour and capital markets, and eventually monetary and fiscal integration. This tends to focus on border measures such as the import tariff. However, supply-side constraints may be more important. A deeper integration agenda that includes services, investment, competition policy and other behind-the-border issues can address the national-level supply-side constraints far more effectively than an agenda which focuses almost exclusively on border measures.