The mechanical and thermal interactions which occur between the cutting tool and workpiece material during the machining processes have a critical influence on the surface and near-surface material properties of the final component. Such machining-induced alterations to the surface integrity of a component can have a critical effect on fatigue performance. By characterising residual stresses, microstructural deformation, and other machining-induced anomalies and linking these to material performance, machining processes can be optimised to ensure that components meet application demands.