This paper is divided into three parts. I begin with a short history of the way American psychiatrists have defined mental disorder in general, and paraphilias (sexual perversions) in particular, from the 1950s to 2013. I look at how the different editions of the Diagnostic and Statistical Manual of Mental Disorders (DSM) have articulated (or in the case of the future DSM-5, will articulate) the distinction between health and disease. In the second part I suggest how psychiatrists might want to modify their approach to the definition of mental disorder. In the third part I explain why the paraphilias in particular should be removed from the current psychiatric classification of diseases.