Technological advances have resulted in the replacement of traditional film-screen mammography with digital mammography, which has been shown to be more accurate in younger women, in those with dense breasts and in pre- and peri-menopausal women [1]. However, one of the major limitations of mammography remains, that is the issue of overlapping breast tissue mimicking or obscuring a lesion. This leads to women receiving unnecessary recalls for further tests (and the associated adverse psychological effects) and to cancers being missed. The introduction of digital mammography has allowed the development of new image acquisition and processing techniques, such as digital breast tomosynthesis (DBT), which promises to overcome some of the limitations of conventional 2D mammography. DBT minimises the effect of tissue superimposition and allows better visualisation of the internal structure of the breast by displaying the tissues in a series of thin contiguous slices. An example is shown in Fig. 30.1a, b.