The Early Social Interaction (ESI) Project (Woods & Wetherby, 2003) was designed to apply the recommendations of the National Research Council (2001) to toddlers with autism spectrum disorders (ASD) by using a parent-implemented intervention that (a) embeds naturalistic teaching strategies in everyday routines and (b) is compatible with the mandate of the Individuals with Disabilities Education Improvement Act (IDEIA) of 2004, Part C. This quasi-experimental study is a preliminary effort by the authors to evaluate the effects of ESI on the social communication outcomes for a group of 17 children with ASD who entered ESI at age 2 years. The results indicated significant improvement on 11 of 13 social communication measures. The researchers compared the ESI group with a contrast group of 18 children with ASD who entered early intervention at age 3 years. The contrast group's results were comparable to those of the ESI postintervention group on communicative means and play, but the contrast group as a whole demonstrated significantly poorer performance on all other social communication measures. These findings offer promise for the use of parent-implemented interventions in promoting social communication for toddlers with ASD.