Since the microstructural origins of radiation-induced toughness degradation are presumed to be identical to those that cause changes in tensile properties, it appears possible to make predictions of residual fracture toughness based on changes in the tensile behavior and the associated microstructural evolution of the steel. A model for tensile-toughness correlations is presented that appears to be valid for radiation-hardened stainless steels. Tensile data from both ducts and cladding tubes of 20% cold-worked American Iron and Steel Institute Type 316 stainless steel irradiated in Experimental Breeder Reactor-II are used to make the prediction that sufficient toughness is retained in this steel for both fast reactor and fusion reactor applications.