The interest of imaging Mammography permits diagnosis of infra-clinical breast lesions with a sensitivity of around 80 %. Moreover, with the improvement of the apparatuses and films, the latter permit analysis of the breast areas in most cases. Sonography, indisputable support for the study of dense breasts, is a complement to mammography and clinical examination. Magnetic resonance imaging is the most sensitive technique, but cannot be used in routine controls. The principle images are essentially opacities characterised by enhanced density in the glandular parenchyma (circular or round, asymmetrical opacities of architectural density and disorganisation, stellar and epiculated opacities) and micro-calcifications without specific appearance, revealing when isolated in situ intra-ductal or micro-invasive lesions. The interest of biopsy procedures For non-palpable tumours discovered on imaging, stereo or radio-guided cytological aspirations are proposed so long as the image is not too small. in the presence of infra-clinical images inaccessible to guided cytology, stereotaxy micro-biopsies can be performed. The relative insufficiency of results obtained has led to the proposal of needles of larger calibre used in an apparatus called a mammotome or in the ABBI system, the latter permitting radio-guided surgical excision. Priority given to clinical controls The technical progress must not lead one to neglect the clinical examination, which, in 5 to 30 % of cases, reveals a cancer when the mammography or sonography does not.