Whole breast irradiation delivering an equivalent dose of 50 Gy in 5 weeks, followed by a 10 to 16 Gy-boost to the tumor bed is the standard of care after breast-conserving surgery for early-breast cancer. Accelerated partial breast irradiation (APBI) is currently under investigations in large multi-institutional, prospective, randomized trials to objectively address the critical endpoints of treatment efficacy, toxicity and cosmesis. Patient's selection for this new approach is crucial to individualise treatments and define the subgroups of patients who will really benefit from APBI in terms of quality of life without decreasing long-term results of the disease control and cosmesis. In this review, we will discuss the patients' profiles selection for APBI regarding their general and tumor criteria. The differences between APBI techniques either performed intra or post operatively will be also discussed.