The deformation microstructures associated with aluminium after shock loading and cold rolling at room temperature and at liquid nitrogen temperature are presented and discussed. A high density of point defects is produced by shock loading aluminium and it is observed that vacancy-produced dislocation loops are more numerous than those produced by interstitial clustering. Comparison is made with the response of copper and nickel to shock and it is shown that aluminium does not form dislocation cell structures as these metals do under similar loading conditions. The temperature of deformation has little effect on the microstructure in the low pressure range, but as pressure increases the temperature of deformation becomes more important. Mechanisms for the production of defects are discussed.