Evaluating the effectiveness of Thabo Mbeki’s political mediation in the Zimbabwean conflict of 2008, following a disputed election outcome, is the principal objective of this study. The Ripeness Theory of mediation and conflict resolution that was proposed by William Zartman and developed by other scholars is deployed as the theoretical framework of the study. The principal measure of the effectiveness of mediation lies in its success in resolving conflict in a sustainable manner. There is consensus in conflict resolution scholarship that the post-cold war era has witnessed a marked shift of conflicts from the inter-state scene to the intra-state domain, such as the one in Zimbabwe, 2008. This shift has brought with it increasing attention to issues of human security, human rights and democratisation in mediation and conflict resolution. As a result, a compelling need for the effective resolution of such conflicts, and guarantee of the enforcement of human rights, security and promotion of democratisation as part of mediation, has arisen. There is also a general acceptance, amongst scholars, that the success of mediation goes beyond the signing of mediated agreements as often case conflict has re-ignited after the signing of peace agreements. For that reason, the argument that mediation is counter-productive as it often puts a lid on the can of conflict without resolving the underlying conflict issues has achieved currency. There is therefore a general convergence of views in mediation literature that addressing the structural causes of disputes guarantees the sustainable resolution of conflict. It is in the context of these developments and views in international relations and politics that this study evaluates, using the Ripeness Theory, its limits noted, the effectiveness of Thabo Mbeki’s mediation in Zimbabwe, and the argument is advanced that often case mediated agreements are not effective mechanisms for the sustainable resolution of conflict and the achievement of democratisation and durable peace. Civil society groups need to be involved to expand the scope of negotiations and limit effects of mediator partiality. / Political Sciences / M.A. (International Politics)