Mental disorders cause suffering for many and pose challenges for the psychiatric profession. Throughout history, the way that society and psychiatry have thought about mental disorders has changed greatly. One area of great difficulty and great change has been psychiatric classification – how psychiatry carves up the realm of mental illness into diagnostic categories. During the second half of the Twentieth Century, the Diagnostic and Statistical Manual of Mental Disorders, the DSM, became the bible of psychiatry, the most influential psychiatric classification system. But through its several editions, criticism has followed the DSM, which serves as a target for debates about how psychiatric diagnosis and research should be done. At the head of these debates have been several philosophers. In today’s consultation, I speak with three philosophers of psychiatry: Rachel Cooper (Professor in the Department of Politics, Philosophy and Religion at Lancaster University), Jonathan Tsou (Associate Professor in the Department of Philosophy and Religious Studies at Iowa State University) and Kathryn Tabb (Assistant Professor of Philosophy at Bard College).