This study is a multivariate empirical analysis of 593 mediation events in international conflicts between 1945 and 1990.The structure of the analysis is based on an explicit conceptual framework of the nature of international mediation.The analysis employs an · appropriate, yet sophisticated, multivariate technique to further our understanding of the dynamics of the forces that bring about successful mediation. Four clusters of variables are examined, relating respectively to the dispute, the parties, the mediator, and the mediation event. From these clusters six key variables are identified: issue type; the power disparity between the parties; the level of fatalities; the relationship between the mediator and the parties; the mediation environment; and the nature of the mediator's strategy. These variables are analysed simultaneously and are found to be reliable determinants of mediation outcome. The analysis breaks new ground by identifying the direct and interactive impacts of these variables on mediation success, and by using these relationships to build a predictive multivariate model of the dynamics of international mediation. From this model a matrix of key mediation forces is generated which enables the prospective mediator to assess his/her likelihood of success in a given situation.