Core Concepts Personality disorders (PDs) are enduring, ingrained, maladaptive patterns of behavior and relating to others that severely impair functioning. Diagnosed only after age 18, traits are inflexible, making treatment slow and difficult. Patients rarely recognize their behavior as problematic, often blaming external circumstances.

The 3 Diagnostic Clusters

• Cluster A (Odd/Eccentric): Paranoid (pervasive mistrust/suspicion), Schizoid (detached, unemotional loners), Schizotypal (cognitive distortions, magical thinking, eccentric behavior).
• Cluster B (Erratic/Dramatic): Antisocial, Borderline, Histrionic (excessive emotionality, attention-seeking), Narcissistic (grandiosity, need for admiration, lack of empathy).
• Cluster C (Anxious/Fea ...