This paper provides an overview of the contributions that plastic methods of analysis can make to the protection of the public and the security of industrial plant against extreme dynamic loading events which involve explosive blast pressures or impact loadings from various projectiles. It is possible, by careful design, to absorb the external dynamic energies through large inelastic deformations of the structural members and specially designed energy-absorbing systems. Both the protection methods are examined briefly, together with some discussion on the dynamic properties of materials, including inelastic failure, and the impact perforation of ductile metal structures. Some phenomena are emphasised that are important for numerical finite-element schemes as well as theoretical methods of analysis.