Despite evidence supporting the use of dialectical behavioural therapy, doubts remain about its efficacy. Miriam Avery and Timothy Bradshaw argue that further research is urgently needed

Caring for service users who have a diagnosis of borderline personality disorder (BPD) can be stressful because they often present with challenging behaviours such as deliberate self-harm. Historically, nurses and other mental health professionals have often held negative attitudes towards such clients, considering them to be untreatable. This article reviews developments in UK mental health policy that have made providing services for service users with BPD a clinical priority. The authors also discuss the emerging evidence for a psychological treatment for BPD – dialectical behavioural therapy – which may improve outcomes for BPD clients.