The document discusses the history and diagnosis of selective mutism. It notes that selective mutism was previously called elective mutism and was added to the DSM-III in 1980. At that time, it was poorly understood and theories blamed parents or trauma as causes. The establishment of the Selective Mutism Foundation in 1991 led to renaming it selective mutism in DSM-IV in 1994 and eliminating unfounded theories by providing research. Placement in the DSM and whether it is an anxiety disorder or communication disorder has been controversial. The document outlines the current diagnostic criteria and classification in DSM-IV-TR.