The distinction is the amount of support required. Level 1 describes individuals requiring support — they may struggle to initiate social interaction and have difficulty with organization, planning, and flexibility, but can function with some assistance. Level 2 describes individuals requiring substantial support — social communication challenges are more apparent even with supports in place, and inflexibility of behavior significantly affects daily functioning. Levels can also be assessed separately for social communication and for restricted/repetitive behaviors, meaning a person may be level 1 in one domain and level 2 in another.