Autism Spectrum Disorder is defined to be a range of pervasive developmental disorders that significantly affect verbal and nonverbal communication and social interaction, generally evident before age three, that adversely affect a child’s educational performance and results in the need for specially designed instruction and related services. Other characteristics often associated with autism are engaging in restricted repetitive activities and stereotyped patterns of behavior, resistance to environmental change or change in daily routines, and unusual responses to sensory experiences. These characteristics may manifest in a variety of combinations and range from mild to severe. Autism Spectrum Disorder may include Autistic Disorder, Pervasive Developmental Disorder Not Otherwise Specified, Asperger’s Disorder, or other related pervasive developmental disorders. The corresponding definition is found in State Board of Education Rule 6A-6.03023, F.A.C.