© Division on Autism and Developmental Disabilities. Children with autism spectrum disorder (ASD) tend to receive several related services during their early school years. In this study, we followed 70 preschoolers with ASD and used parent reports to document the intensity of these services over a 4-year period, in relation to children’s outcomes in three domains. While behavioral difficulties improved, social skills and adaptive abilities in children with ASD tended to remain impaired across development. We found that very young children with ASD received behavioral services regardless of need and overall standardized measures of behavioral difficulties showed improvement over 4 years. Further, over time, behavioral services were correlated to children’s needs. Standardized measures of social skills improved significantly but scores remained impaired and services specific to this skill area were few. Adaptive abilities remained significantly impaired however, and adaptive services were very few, with little relationship to abilities over time.