Abstract
This paper emphasises the role that dislocation pile-ups have in promoting instability that leads to shear banding‚ and the Dillamore formalism is used to demonstrate their importance. The model is capable of being applied to both laminar structures and particle hardened alloys. By incorporating the idea of a critical length in which shear band branching can dissipate shear imposed from neighbouring grains‚ it is possible to estimate the rolling strain at which shear banding changes from being grain scale to sample scale.