AUTISM, A SERIOUS DEVELOPMENTAL DISORDER that presents in children before the age of three, has a history of diagnostic confusion, prognostic uncertainty, and a never-ending array of treatment options. It is not at all unusual for parents to receive conflicting diagnoses if they take their atypical preschool child to several different professionals. Autism, nonautistic pervasive developmental disorder (PDD or PDD-NOS), mental retardation, developmental language disorder, attention deficit with or without hyperactivity, emotional disturbance, or static encephalopathy may be diagnosed—all in the same child. No wonder the parents are perplexed, frightened, and, in most instances, devastated. After receiving a diagnosis of autism, parents are faced with the twin dilemmas of where to turn for a fuller understanding of this disorder and how to decide which kind of treatment would be best for their child. The choice of treatment is, of course, critical, and there are many options to choose from. One could, for example, select a behavioral therapist; a school or clinic