In today's world, reasonably predictable military operations have been replaced by low intensity conflicts-less predictable terrorist activities carried out by determined individuals or small groups that possess a wide range of backgrounds and capabilities. Because of the threats posed by this evolving type of warfare, civil engineers and emergency personnel face new challenges in designing facilities to protect lives and property and in conducting effective rescue operations and forensic investigations. Addressing these needs, Modern Protective Structures develops realistic guidelines for the analysis, design, assessment, retrofit, and research of protected facilities.