Children must be between 2 and 4 years, 11 months of age at enrollment
Confirmed diagnosis of autism spectrum disorder based on standardized diagnostic assessments and clinical judgment
Demonstrated significant language delay as determined by standardized language measures
Ability to participate in study assessments and intervention procedures
At least one English-speaking parent or caregiver available to participate in parent training and research measures
Receiving stable community-based treatments or medications for at least one month prior to baseline, with no anticipated changes during the study period
You may not be if
Current or lifetime diagnosis of a severe psychiatric disorder (e.g., bipolar disorder)
Presence of an active or unstable medical condition (e.g., uncontrolled seizure disorder or significant cardiac disease)
Child's primary language is not English
Prior adequate trial of PRT or ESDM
Receipt of more than 15 hours per week of in-home applied behavior analysis services
Inability to complete study assessments or procedures to obtain valid data
