For the diagnosis of ASD is carried out successfully it is essential that the health professional has enough experience in the subject and who understand deeply about the childish behavior in general. In addition, it needs to be very attentive to the life history of the patient, which should begin even before the child is born, including so the pre-christmas season, the training of the child in the womb and the birth. Until the moment, there are no examinations or psychological tests that determine if the child is or is not within the spectrum of autism, but are currently used in the diagnosis some instruments described in the DSM - V: the Scale of assessment and the traits of autism (ATA), the Inventory behavior autísticos (ABC), the Questionnaire for the verification of autism (ASQ), the diagnostic Criteria for autism disorder, the diagnostic Criteria for Asperger disorder and Criteria for diagnosis of disorder and global development, without other specification.