Ductal carcinoma is situ (DCIS) is the fastest growing subtype of breast cancer, mainly because of improved screening activities. In contrast to invasive disease, DCIS is a local process with excellent survival rates. Current treatment strategies include surgery, radiotherapy (RT) and anti-hormonal treatment. The selection of an individual risk-adapted therapeutic approach remains controversial. This relates especially t-o the extent of surgery and the therapeutic index of adjuvant RT and tamoxifen. Several new trials have been published or updated recently that address important clinical issues. There is an urgent need to get more insight into the biological behaviour of different subtypes of DCIS, and develop more targeted and individualized treatment strategies. So far, surgery appears to be the most effective treatment modality. A morphology-based treatment model that allows complete resection of certain DCIS lesions without further adjuvant measures has not been evaluated prospectively and deserves further evaluation.