The purpose of this paper is to summarize the results of a survey of the unclassified literature made to determine the effects of neutron bombardment upon the mechanical properties of structural materials. Structural materials—as the term is used herein—are those metals and alloys which contain neither fissionable nor fertile materials and which are used in reactor applications exposing them to neutron bombardment. It is hoped that the information and opinion presented in this paper will prove of some use to metallurgists and mechanical engineers interested in radiation damage to reactor components—especially those who have recently become associated with a nuclear reactor development program and who are newly confronted by the problem.