Autism spectrum disorder (ASD) is a neurodevelopmental difference that can appear in many forms. The three levels of autism are based on the amount of support an autistic person might want or need. The three levels of autism are:

• Level 1: Requiring support: A person with level 1 autism requires the least amount of support. This is the mildest form of autism, which includes those who would have previously been diagnosed with Asperger’s syndrome. Individuals with level 1 autism may have difficulty understanding social cues and may struggle to form and maintain personal relationships. They may understand and speak in complete sentences, but have difficulty engaging in back-and-forth conversation.

• Level 2: Requiring substantial support: An autistic person at level 2 might need school accommodations like scribing or reading support, as well as an educational assistant nearby to help with social interactions during recess and lunch breaks. They may also have schoolwork adapted to their level and be part of a social skills group. While in high school, they might participate in an off-campus job training program. Outside school, an autistic person at level 2 might benefit from activities such as speech therapy, occupational therapy, social skills coaching, and applied behavior analysis (ABA) therapy.

• Level 3: Requiring very substantial support: Level 3 is the most severe form of autism. An autistic person assessed as level 3 in either social communication or restricted/repetitive behaviors will need the most support and seem noticeably different at a young age. Level 3 social communication means the person may be nonspeaking or have echolalia (repeating words or phrases they hear). Individuals with level 3 autism exhibit marked inflexibility of behavior, with extreme difficulty coping with changes to routine. At this level, restrictive or repetitive behaviors interfere with the individual’s ability to function. Changing focus from one activity to another may come at great difficulty and cause significant distress. People with this level of autism might use augmentative and alternative communication (AAC), like a speech-generating device or Picture Exchange Communication System (PECS) .