In BPD, dissociative experiences are highly common, but also very diverse in their manifestations and severity. Acute dissociative symptoms typically occur during emotional stress, often together with psychotic or psychotic-like symptoms. Chronic dissociative symptoms are often intertwined with other BPD features, such as reduced emotional awareness, identity disturbances, and self-harming behaviour. Therefore, dissociation may be either overlooked or considered a mere consequence of distress. However, research suggests that dissociation is not merely a learned stress response or maladaptive coping mechanism, but also a predisposition to more serious problems in emotion regulation, identity disturbances, and interpersonal conflict. When assessed in daily life, dissociation was not only triggered by stress, but also worsened affective instability and relationship problems. Dissociation appears to be more severe and persistent in individuals with adverse childhood experiences, long-lasting trauma, and co-occurring mental health conditions. Neurobiological and experimental studies suggest that dissociative states are associated with a hyposensitivity to pain and social threat, possibly due to dampened autonomic arousal and limbic reactivity, as well as impaired emotional learning and memory. Findings underline the need to understand dissociative symptoms in a broader biosocial framework and to carefully evaluate their individual manifestations, functions, and possible impact on everyday life and treatment.