Antisocial personality disorder (ASPD) is a complex disorder that creates a diagnostic, ethical, and treatment dilemma for mental health professionals. Psychosocial, biological, and cultural influences play a role in the development of ASPD. People with ASPD often had harsh early childhoods that impaired their ability to trust in adulthood. Research supports intriguing biological links, but it remains unclear if biological differences are the cause or the effect of ASPD. Individualism, patriarchy, and widespread media violence create the cultural context for the development of ASPD. ASPD is difficult to clinically diagnose and treat, and there is controversy concerning whether ASPD is a psychiatric or a legal-ethical problem. However, the management of ASPD often falls to mental health services. This article addresses treatment and primary prevention of ASPD in a way that is relevant to mental health practice.