Borderline personality disorder (BPD) is therapeutically challenging for psychiatrists and psychotherapists. The difficulties we are met with are closely related to the key dimensions of this disorder: a perturbed sense of identity, emotional dysregulation, perturbed impulse control and interpersonal relationships marked by a tendency to idealisation and devaluation. The healthcare we provide is therefore characterised by heightened emotional intensity, frequent acting out, in particular in a self-damaging or suicidal manner, and early therapy discontinuations. These challenges have contributed to the emergence of specialised therapies. Among these, the mentalisation-based therapy (MBT) developed by Bateman and Fonagy has garnered a significant amount of interest. This study provides a short review of borderline personality disorder and mentalisation-based therapy, and goes on to describe the work conducted to adapt and import MBT into French. It concludes by describing the perspectives that the treatment offers in terms of our clinical practice as we work with patients suffering from borderline personality disorder, but also with other patients.