SummaryBorderline personality disorder (BPD) is a leading candidate for developing empirically based prevention and early intervention programmes because it is common in clinical practice, it is among the most functionally disabling of all mental disorders, it is often associated with help-seeking, and it has been shown to respond to intervention, even in those with established disorder. Moreover, it can be reliably diagnosed in its early stages and it demarcates a group with high levels of current and future morbidity and mortality. Data also suggest considerable flexibility and malleability of BPD traits in youth, making this a key developmental period during which to intervene. Novel indicated prevention and early intervention programmes have shown that BPD in young people responds to intervention. Further work is required to develop appropriate universal and selective preventive interventions.