The energy-balanced approach is used in this study to evaluate the local effects of nondeformable missiles on concrete structures in terms of penetration depth. For nondeformable missiles, the kinetic energy of the missiles is dissipated into local strain energy in terms of penetration, back-face scabbing, or perforation, as well as overall structural response. This study confirms that the energy dissipation due to the overall structural response is very small compared to the local effects in most cases, and can be neglected. The energy-balanced approach is a viable alternative approach to estimate the penetration depth of nondeformable missiles striking concrete structures. The equations proposed in this paper can be used for this purpose. Once the penetration depth is known, the target thickness necessary to prevent back-face scabbing can be easily estimated.