This document provides information on avoidant personality disorder (APD), including its definition, core features, symptoms, causes, prevalence, comorbidities, and treatment options. APD is characterized by extreme social inhibition, feelings of inadequacy, and sensitivity to criticism or rejection. Symptoms include avoiding occupational and social activities, unwillingness to get close to people, and being preoccupied with feelings of inhibition. While the exact causes are unknown, genetic and environmental factors may play a role. Treatment typically involves psychotherapy like interpersonal therapy as well as antidepressant or anti-anxiety medication.