According to Fiedler's Contingency Model of Leadership Effectiveness, group performance is a function of the leader-situation interaction. A review of past validations has found several problems associated with the model. Meta-analytic techniques were applied to the Contingency Model in order to assess the validation evidence quantitatively. The 33 tests used by Fiedler to derive the model and 127 subsequent tests of the model's validity were examined. Results of the meta-analytic computed on Fiedler's original studies indicated overall support for Fiedler's derivation. Analysis of Fiedler's 1978 review of the validation evidence for the Contingency Model found overall support for the model when field and laboratory studies were combined. Analysis of other direct tests not included in Fiedler's review also provided overall support for the model. Analyses of extension studies and investigations which examined the model in relation to training and co-acting groups indicated strong support for the model. The model was found to be an excellent predictor of group performance. The use of meta-analytic techniques appears to identify the directions that theory and research should take in the development of the Contingency Model. (NRB)