Does Borderline Personality Disorder belong in the same category as narcissism, sociopathy, and psychopathy, or should it be grouped with trauma-related conditions such as Complex PTSD and PTSD?

As a practicing psychologist in Bulgaria, I often see this question arise — not only from clients, but even among professionals. The confusion largely comes from the fact that diagnostic systems vary. The DSM, widely used in the US, and the ICD, more common in Europe, do not always classify disorders in the same way.

In my work, I draw on a developmental and psychodynamic understanding of personality, incorporating object relations theory and the concept of the self. My approach has been influenced by the work of James F. Masterson, while also integrating elements from Gestalt therapy and modern trauma-informed practices.

How Masterson grouped personality disorders

In his framework, there are three main personality disorders that respond well to psychotherapy:

1. Borderline Personality Disorder (BPD)

2. Narcissistic Personality Disorder

3. Schizoid Personality Disorder

Psychopathy and sociopathy were not included in this group — not because they don’t exist, but because they generally require different strategies, and the evidence for success with standard psychodynamic approaches is limited.

The role of trauma in personality disorders

Most individuals with personality disorders have some history of early emotional or relational trauma. However, this does not make BPD a trauma disorder in the strict diagnostic sense.

Example:
A woman with BPD may have grown up in an emotionally inconsistent or neglectful home. This shaped her sense of self and her relationships long before any specific traumatic event occurred. Later in life, she might experience something acutely traumatic — such as sexual assault — which could worsen her symptoms. Yet the foundation of the personality disorder was laid in early childhood.

How trauma disorders differ

• Personality disorders emerge during the formative years of personality development, usually in early childhood.

• Trauma disorders (PTSD, CPTSD) can develop at any age following one or more traumatic events.

It’s possible for someone to have both, but one does not automatically cause the other.

Why this distinction matters

A diagnosis is not a label — it’s a tool for identifying the most effective treatment.

• BPD often benefits from deep psychodynamic therapy, sometimes alongside structured approaches like Dialectical Behavior Therapy (DBT).

• PTSD and CPTSD require trauma-specific interventions, such as EMDR, somatic experiencing, or trauma-focused cognitive-behavioral therapy.

Final note

Borderline Personality Disorder belongs in the same group as other treatable personality disorders, such as narcissistic and schizoid personality disorders. While trauma often plays a role in its development, BPD is not the same as a trauma disorder. Clear differentiation helps ensure that clients receive the kind of therapy that can truly address their needs.