A finite element formulation which derives constitutive response from crystal plasticity theory was used to examine localized deformation in fcc polycrystals. The polycrystal model was an idealized planar array of 22 hexagonal grains. The constitutive description used is based on a finite strain kinematical theory that accounts for lattice rotations. Formation of shear bands was successfully modeled in both single crystal and polycrystals. Stress and strain distribution around triple junctions was also analyzed. Results show the distributions of stresses and strains are distinctly inhomogeneous. Stress and strain fields across grain boundaries are highly discontinuous. However, this discontinuity will be restrained when shear bands are fully developed. A finite element formulation which derives constitutive response from crystal plasticity theory was used to examine localized deformation in fcc polycrystals. The polycrystal model was an idealized planar array of 22 hexagonal grains. The constitutive description used is based on a finite strain kinematical theory that accounts for Lattice rotations. Formation of shear bands was successfully modeled in both single crystal and polycrystals. Stress and strain distribution around triple junctions was also been analyzed. Stress and strain fields around grain boundaries are also highly discontinuous However, this discontinuity will be restrained when the shear bands are fully developed.