ABSTRACT This report presents a general method of predicting and bounding casualties from both prompt and delayed effects produced by attacks against population. The method contains analytic submodels for distributions of population and hardness and for nuclear weapons phenomenology. Relocation schemes which evacuate people to locations where at least some people already reside are characterized abstractly and analyzed parametrically. The general analytic results predict the dispersion/hardness needed to achieve any specified outcome against any specified attack size and are used to explore the relative influence of the ingredients of a passive defense system.