In this qualitative study, 11 mothers of toddlers with autism participated in interviews to investigate how they perceived their roles and their competency to support toddlers' social learning in the context of both professional-implemented and parent-mediated early intervention models. The authors conducted a thematic analysis with multiple layers of independent coding. Four resulting themes highlighted challenges and contributors to parent self-efficacy. First, related to child characteristics, challenges were most prominent in the early period as participants adjusted to the diagnosis and reached to connect when social difficulties emerged. Second, having a peripheral role in early intervention challenged participants' confidence in their abilities, while receiving guidance to assume an active leadership role supported their sense of efficacy for facilitating toddlers' social learning. In a third theme, participants described specific and general examples of their expertise. Fourth, participants considered the transactional context of parent–child interaction and largely viewed their toddlers' independent wills, natures, and preferences as strengths upon which to build social engagement. The results support the need for early interventionists to promote and leverage family capacity for facilitating toddler learning as social challenges begin to appear for toddlers with autism. Parent-participatory early intervention practices are linked to parents' positive views of their own and their children's capabilities, beliefs that are associated with a range of parent and child outcomes. A qualitative study was conducted with 11 mothers of toddlers with autism who had experience with both professionally directed and parent-mediated early intervention. Participants were interviewed to explore their perspectives on their roles in relation to professionals and on how they viewed their ability to support their toddlers' social learning. An in-depth analysis of the transcribed interviews resulted in four themes. First, in the early stages, participants experienced challenges to their self-efficacy as they adjusted to the diagnosis and reached to connect with their child when social challenges emerged. Second, participants' views of their capability were stronger when they were provided with background knowledge enabling them to take the lead in guiding their children's learning than when professionals modeled predetermined intervention strategies for them to copy. Third, participants provided specific examples of their expertise to support their toddlers' social learning and viewed their close parent–child relationship and intimate knowledge of their children as valuable to the intervention. Fourth, participants voiced respect for their toddlers' natures and preferences, positioning them to build on their toddlers' strengths in everyday interactions. The results support the need for early intervention providers to promote and leverage family capacity for facilitating toddler learning as social challenges begin to appear for toddlers with autism. [ABSTRACT FROM AUTHOR]