Purpose: Early social experiences and language environments are critical for infant brain development, language acquisition, and health outcomes. Pediatricians have long recognized their unique opportunity to educate parents about the importance of fostering enriched home language environments in order to address health and academic disparities. More research is needed to better understand knowledge among professionals who serve families with young children. The present study examined knowledge and practices among pediatricians and pediatric trainees (PED) in comparison with early childhood educators (ECE), professionals who play a significant role in reaching parents of young children early in their children’s life. Methods: Online surveys were administered to PED and ECE through the 2017 AAP National Conference and the 2017 Head Start Conference, respectively. On a voluntary basis, respondents reported basic demographics and completed the Survey of Parent/Provider Expectations and Knowledge (SPEAK), assessing knowledge of infant (0-6 months) and early childhood (0-5 years) cognitive and language development. Low-SES primary caregivers (PCG) in Chicago also completed these surveys during their newborn’s 1-week well-child visit. Results: Participants included 331 PED, 292 ECE, and 467 PCG. ECE were most knowledgeable about cognitive and language development (Table 1). 76.2% PED and 79.7% ECE reported learning about early childhood cognitive and language development from education and/or training; they were significantly more knowledgeable than those who never had such learning experience (Table 2). ECE who had more work experience as well as those who worked with younger children were more knowledgeable (Table 2). PED who were more knowledgeable started discussing early learning and language development with parents earlier in the child’s life and more often (Table 2). Conclusions: Receiving coursework in cognitive and language development was associated with enhanced knowledge among all professionals, indicating the significance of its implementation throughout their training. These findings also suggest the possibility of establishing interdisciplinary partnerships between PED and ECE, who are more knowledgeable of early childhood development and more experienced working with young children in educational settings. Importantly, as PED became more knowledgeable, they were more likely to start discussing cognitive and language development early with parents; this is perhaps due to better recognition of the importance of early learning and language environments for young children’s development, and a better aptitude for explaining these topics to parents, which can be difficult. The knowledge gap between professionals and low-SES parents illustrates the need for more support being made available to these parents. By taking advantage of their unique relationships with the parents, PED and ECE have can empower low-SES parents to foster environments that maximize their young children’s cognitive potentials.