Beginning in fall, 2016, the UC Davis pediatric cohort, ReCHARGE, was funded with the new Environmental Influences on Child Health Outcomes (ECHO) Consortium that encompassed close to 80 sites. Now in year 7 of ECHO Phase 1, UC Davis has enrolled ~900 children into ECHO from three neurodevelopmental groups of children with: autism spectrum disorder (ASD), developmental delays (DD) without autistic symptoms, and typical development (TD); uploaded over 55,000 data collection forms to the ECHO Cohort Data Platform, and transferred over 8000 biospecimen aliquots to the ECHO Biorepository, including DNA for SNP arrays, urine for analyzing novel chemicals from common but understudied household products, and blood for multiple uses. The UC Davis ECHO team led a number of analysis proposals, authored/co- authored 40 peer-reviewed papers, with another 50 in-progress. The Team also contributed to developing ECHO policies and participated in and led various working groups, such as Neurodevelopment, Chemical Exposures, Epigenetics, as well as Committees on Publications, Policy Implementation and Evaluation, and others. The ECHO-ReCHARGE cohort focuses on the ECHO area of neurodevelopment, which is facilitated by the UC Davis MIND Institute. In ECHO Phase 2, the UCD Aim 1 will: examine environmental, social, and biologic exposures in associations with externalizing and internalizing behaviors, namely, symptoms of ADHD, anxiety and depression at ages 8-20; and identify both synergistic relationships between environmental and social factors, especially environmental justice and social justice, and potential modification of exposure-outcome associations by early childhood developmental diagnosis (ASD, DD, TD), age, sex and puberty status. Aim 2 will evaluate the same exposures, plus measures of PFAS and plasticizers for associations with longitudinal trajectories of the above behavioral and emotional outcomes, as well as cognitive skills. In both aims: environmental exposures include air pollution, greenspace, and home product use; social factors are neighborhood SES, family financial hardship, race, ethnicity, and parental mental health or substance use problems. Aim 3 will implement the final ECHO protocol with high fidelity, maximize retention, and adhere to all ECHO policies, IRB, HIPAA and other regulations. UCD will continue to contribute broadly to the ECHO infrastructure; advance the science through analysis and publications; promote diversity and equity through our research questions, workforce, and retention strategies; and actively participate & play leadership roles in this high-profile, unique program to discover underlying risk and resilience factors for childhood health and development.