There is a wide range of problems in geophysics, from earthquake prediction to the driving forces of plate tectonics, where it is necessary to understand how rocks deform. The material science approach to understanding these geophysical processes is based on the premise that the macroscale behaviour of rock is governed by microscale interactions. Rock, as a material, will deform under an applied stress elastically, plastically, by fracturing and brittle (cataclastic) flow, and frictional sliding on a fault. The magnitude and direction of the applied stress, the rate and duration of loading, ambient pressure and temperature, the presence of fluids and previous deformation history all control the overall mechanical response. Deformation can be remotely monitored by physical measurements such as elastic wave velocities and electrical conductivity. The emerging subject of rock physics seeks to integrate the disciplines of rock mechanics with rock physical property measurements. The challenge for rock physics is to understand through experiments and modelling, microscopic rock behaviour and apply this to large–scale phenomena. The future is in holistic laboratory experiments, where a wide range of physical parameters is measured concurrently during the deformation experiment. This is important not only in a material science sense, but crucially these parameters are monitored by geophysical techniques and so laboratory experiments can be related to crustal processes. This paper reviews how the material science approach is applied to problems in geophysics (particularly for brittle deformation), the experimental methodologies employed and how the question of scaling from the laboratory to a planetary scale is addressed. This approach is considered in terms of the evolution and dynamics of the Earth'crust and its ice sheets as they represent the components of the solid Earth with which humankind directly interacts.