This document outlines the modules of a training series on autism spectrum disorders. It defines autism as a brain-based disorder that affects social interaction, communication, and causes repetitive behaviors. There are three main types of autism spectrum disorders: autistic disorder, Asperger syndrome, and PDD-NOS. Autism affects each person uniquely and is more commonly diagnosed in boys than girls. While the causes are unknown, the prevalence of autism has been rising in recent decades.