According to Appelbaum, his focus has always been on "trying to address the empirical questions that... inform and influence policy-related decisions." the understanding of the influence of law on psychiatry, and the prediction of dangerousness so as to better guide psychiatric practice. His original work with
Tom Grisso in the assessment of patient competency has had broad influence for research and better treatment of both civil and criminal patients. He developed a theory of ethics for forensic psychiatry. Since moving to Columbia College of Physicians & Surgeons in 2006, Appelbaum has focused on the medical, ethical and legal aspects of human genetic research. He leads the Center for Research on the Ethical, Legal and Social Implications of Psychiatric, Neurologic and Behavioral Genetics. Appelbaum is a frequent media commentator on medical issues. The New York Times describes him as "a professor of psychiatry at Columbia who has published widely on medical ethics and the law." ==Awards, honors, memberships==