As part of a larger project into the interactions of shock with grain boundaries, calculations that show a localization of energy in some configurations were performed. The verification and prediction of these localizations become important, due to their role in the initiation of a variety of significant material process. The prototype problem is a single grain boundary, inclined to the direction of shock propagation, separating regions of differing orientation. The calculations are made with a finite volume code using a continuum material model with explicit elastic, and plastic anisotropy. The response of NiAl is simulated using material property data from published sources, and from new experiments performed as part of the over‐all project. The localization is seen internally as a small region of higher pressure at the intersection of the shock and the grain boundary. At the breakout surface the localization becomes manifest in velocity and displacement excursions at the grain boundary. This surface phenomenon provides an observable that can be used, with planned experiments, to validate the predictive behavior of the model. © 2004 American Institute of Physics