Multimodal methods of three-dimensional (3-D) imaging of breast cancer are described. These involve scanning confocal microscopy, using 50 MHz acoustic or near-infrared images, four-view (tetrahedral) radiography and x-ray projection microscopy. Computerised volume data from these techniques can be used to produce three-dimensional images of tissue ranging from 500 microns to approximately 4 mm in thickness. Preliminary findings indicate that stereoscopic images or 3-D computerised reconstructions are capable of advancing the understanding of the structure of ductal carcinoma in situ, lesions simulating microinvasive breast carcinoma, surgical clearance of high-grade calcifying ductal carcinoma in situ, and the 3-D growth patterns of invasive forms of breast carcinoma. In the future computerised image fusion techniques seem likely to be able to take advantage of multimodal imaging of breast cancers, thus correcting primary imaging artefacts, improving robustness, and combining complementary information. In addition, the use of computerised tetrahedral radiography may change the intraoperative assessment of breast cancers, which mostly depend at present upon subsequent laboratory procedures that take days to perform.