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The formation and accumulation of microdamage in bone plays animportant role in the occurrence of stress and fragility fractures as well as in theinitiation of bone remodelling. In this study a novel technique is presented for theinvestigation of bone microdamage and crack morphology using laser scanningconfocal microscopy and sequential labelling with chelating fluorochromes. Compacttension fracture specimens machined from bovine tibial cortical bone, weremechanically tested in a wedge loaded crack-propagating tool. Sequential labellingwith xylenol orange and calcein allowed for the crack propagation and microdamageprogression to be assessed at each stage using confocal microscopy. Both two-dimensional confocal images and three-dimensional z-series reconstructions displayedthe formation of a microdamage process zone and wake surrounding the main crack.Further imaging demonstrated the significance of the bone microstructure, such as thevasculature and osteocytes, in the distribution of the microdamage.