In this monograph, first, I argue that democratization in sub-Saharan Africa can be successful, even if the government remains dominated by one major political party. Indeed, a competitive opposition party (even if too weak to take power) can force the dominant government party to be more responsive to voter demands overall and to limit clientelistic practices. This thesis stands in contrast to much of the recent literature on democratization in Africa, which generally views dominant government parties as incompatible with democratic consolidation and responsiveness. Second, I argue that the most important factor for explaining competitiveness degrees of contemporary opposition party systems in African dominant party systems lies in historical legacies of cleavages around the time of independence that were able to spill over into contemporary third wave party competition. These arguments are tested in a mixed-methods design, which is based on a quantitative analysis of 53 elections in 18 third wave African dominant party systems and an ensuing in-depth model-testing comparative analysis of four crucial cases: The dominant party systems of Botswana and Lesotho and the formerly dominant party system of Ghana, as well as the formerly “almost-dominant party system” of Mali. The analysis makes use of comparative history and survey-based measurements of party positions and voter preferences.