Carbon fibre composites have exceptional strength to weight ratios but are inherently sensitive to flaws and localized damage. This typically leads to large safety factors and an under-exploitation of material capabilities. In this study, high resolution phase contrast tomography and through average diffraction strain mapping will be used to characterise in-situ compressive loading of carbon fibre coupons prepared using different edge treatments and containing different types of internal damage. These results will provide high resolution insight into the damage evolution and strain redistribution induced between fibres during loading. Such insights are critical in helping design damage-tolerant composites and in defining more effective criterion for non-destructive damage assessment, with the overall goal of improving composite performance and reliability.