In the second and third years of study recruitment of the HEALthy Brain and Child Development (HBCD) Study, at least 75% of the overall sample is expected to be enrolled and retained. Critical areas of study operations have been identified as important to meeting the overall study objectives in this time period. Mitigation of these gaps requires additional dedicated resources and staffing. This supplement is designed to enact a comprehensive plan to address these gaps in a timely manner within the HBCD Administrative Core. The supplement will provide support for three key components of such a plan: 1) Enhancement of the Study Navigator Program in HBCD to support faculty level leadership to formally evaluate and recommend revisions to the Navigator protocol; to ensure that each recruitment site supports at least one dedicated Navigator; and to formalize core training components for the program, 2) Improvement in oversight and efficiency of the Spanish Language and Culture components of the study across all domains by supporting a faculty level Spanish Language and Culture Committee Chair, and by providing centralized coordination and consistency of translation services across all study components to improve accuracy, equity and inclusion, 3) Acceleration of recruitment overall and in specific target demographics to achieve study objectives at the site level by identifying and evaluating success of novel recruitment strategies and venues. Successful completion of these aims will ensure that the HBCD Study enters into the second phase of longitudinal follow-up with a strong foundation in terms of the overall sample characteristics, and participant support in terms of retention. This study is part of the NIH’s Helping to End Addiction Long-term (HEAL) initiative to speed scientific solutions to the national opioid public health crisis. The NIH HEAL Initiative bolsters research across NIH to improve treatment for opioid misuse and addiction.