Autism is one of the most hotly debated disorders listed in the current Diagnostic and Statistical Manual (DSM), eliciting passionate and often conflicting opinions among health professionals, medical practitioners, parents and researchers. Despite moving on from the early and notorious 'refrigerator mother' pathogenic theories (where autism was said to be caused by emotionally distant parents) to more modem epigenetic conceptualisations (where autism is viewed as being caused by an interaction between a genetic susceptibility and an environmental trigger), surprisingly little has changed in regards to autism as a diagnostic construct. The exclusive use of a triad of behavioural indicators (impaired social interaction and communication, and restricted and repetitive behaviour) to diagnose autism appears to be increasingly out of step with contemporary research into 'biomarkers' or biomedical aspects of the condition. An understanding of the tensions and conflicts surrounding autism is critical in order to fully appreciate tlte conservative nature of information provided in the DSM. This chapter will touch on some of the controversies as they apply to the inclusion of autism in the DSM, ultimately, leading us to consider the most controversial question of all: Does autism belong in the DSM at all?