This study examined the effects of an intervention to support parents and promote skill development in newly diagnosed toddlers with ASD. Participants included 50 children with ASD under 3 and their parents who were randomly assigned to participate in a 6-month intervention, Family Implemented TEACCH for Toddlers (FITT) or 6 months of community services as usual. FITT included 90-min in-home sessions (n = 20) and parent group sessions (n = 4). Results revealed significant treatment effects on parent stress and well-being, with families in the FITT group showing decreased stress and improved well-being over time. While no treatment effects were found for global child measures, there were significant treatment effects on social communication skills.