This Discussion Paper is another result of the project “Liberation and Democracy in Southern Africa” (LiDeSA), which was coordinated at the Institute between 2001 and 2006. The papers are revised versions of presentations to a Session of the Research Committee “Comparative Sociology” at the XVI World Congress of Sociology held at the end of July 2006 in Durban. They explore the role of opposition parties under different aspects in several East and Southern African countries, which differ according to the socio-political determinants.