Persons suffering from Autism Spectrum Disorder may stare vacantly, ignore other people in their social environment, and may exhibit stereotyped movements, such as rocking back and forth. Confirming a diagnosis of Autism Spectrum Disorder usually requires input from other specialists, such as a pediatrician, a professional who specializes in developmental and learning disorders, and a speech/language specialist. Dr. Gray began by describing what she knows of Jacob's difficulties from reading the teacher's written report. After hearing the psychologist's summary of Jacob's behavior problems at school, Mrs. T expresses some surprise at the extent of his problems but acknowledges that Jacob, her youngest, has been by far the most challenging of her four children to parent. Jacob's more dramatic symptoms are usefully understood as his attempts to avoid becoming overwhelmed by a confusing or threatening situation. Behavior modification was used to shape skills that Jacob could learn to apply in natural settings.