The excellent high temperature properties of Ni-base superalloys are derived from the presence of fine precipitates of the intermetallic Ni3Al phase, termed gamma prime. The size, distribution and morphology of these precipitates strongly influence the properties of these alloys and their coarsening during component service is known to lead to a significant deterioration in mechanical properties. It is proposed that a SANS experiment be conducted to characterise the changes that occur in the particle size distribution of gamma prime in a modern nickel-base superalloy used for turbine discs in commercial aeroengines. The data obtained will be used to validate and test predictions from numerical models of precipitate growth.