Minimally invasive therapy has been explored as a potential means of treating breast tumours with minimal disruption to adjacent soft tissues. The purpose of this is to facilitate improved cosmesis and to offer treatment to women who are unfit for surgery. A number of treatment modalities including thermal therapies (intersitital laser photocoagulation, radiofrequency, focused ultrasound and cryotherapy), percutaneous excision and interstitial radiotherapy are being developed. The experience to date of each of these modalities is described and reviewed. Currently there are too few data to indicate the efficacy of these treatments although the preliminary data are encouraging. The need for large-scale studies examining the role of MIT in relationship to the overall management of breast cancer (including chemotherapy, radiotherapy, and the management of the axilla) and outcome is discussed.