Why is psychiatry such big business? Why are so many psychiatric drugs prescribed, and why, without solid scientific justification, has the number of mental disorders risen from 106 in 1952, to around 370 today? In this talk, Dr James Davies takes us behind the scenes of how the psychiatrist’s bible, the DSM, was actually written – did science drive the construction of new mental disorder categories like ADHD, major depression and Aspergers? ‘ or were less-scientific and unexpected processes at play? His exclusive interviews with the creators of the DSM reveal the answer.