Introduction. Informal Primary Caregivers (IPC) of people with borderline personality disorder (BPD) experience a significant burden, making it important to determine their specific needs. Objectives. Cross-sectional study aimed at adapting and establishing the reliability of the Questionnaire on the Needs of Family Members of People with Severe Mental Disorders to identify felt and unfelt needs that may or may not have been met in IPCs of patients with BPD and suggest intervention strategies to effectively address them. Method.