Breast cancer is a rare disease in young women. Its incidence has remained remarkably constant over the last decades, contrary to what has happened in older patients. Age is a major prognostic factor for local control after breast-conserving treatments, which does not seem to be entirely explained by the poor prognostic features that are more commonly associated with breast cancers in young women. A better knowledge of the prognostic factors for local control, and, whenever possible, those pertaining specifically to the young age group, is key, not only to better select the patients who would benefit the most from a breast-conserving approach but also to enhance the local control when this option has been elected. These prognostic factors can be related to the patient, the tumor and the treatment they receive. Finally, we will present a perspective of what the future could hold, both in terms of the selection of the patients and of a more customized therapeutic approach.