A hierarchical computer simulation model which took account of spatial and temporal correlations in the production and diffusion of defects was used to investigate the production of freely migrating defects in irradiated aluminium. The approach used classical molecular dynamics with the embedded atom method potential to investigate the primary damage state from displacement cascades and a kinetic Monte Carlo simulation to follow defect kinetics over macroscopic time scales. Here, this approach was used to investigate the primary damage state and the fraction of freely migrating defects in pure Al as a function of irradiation particle energy and crystal temperature. The results were compared to other face-centered cubic metals and to the experiments when available. Defect Production and Damage Evolution in Al: a Molecular Dynamics and Monte Carlo Computer Simulation. A.Almazouzi, M.J.Caturla, M.Alurralde, T.Diaz De La Rubia, M.Victoria: Nuclear Instruments and Methods in Physics Research B, 1999, 153[1-4], 105-15