New strategies for adjuvant radiotherapy of early breast cancer are being investigated in several phase III randomised trials at the present time. Accelerated partial breast irradiation (APBI) is a way to offer an early breast cancer patient, who has had breast conservative surgery, an adjuvant radiotherapy of short duration aimed at the tumour bed with a certain margin. The rationale of this strategy is that most local recurrences appear close to the tumorectomy cavity and a wish to spare the patient late radiation morbidity. This review discusses the background for APBI, the different techniques, and we highlight possible pitfalls using these techniques. A systematic overview of all phase I and II studies is provided. Patient selection for this therapy is pivotal and based on evidence from previous studies on patient/tumour characteristics and pattern of local recurrences we propose inclusion criteria for patients in APBI protocols.