ABSTRACT Molecular, Cellular and Developmental Dynamics (MCD2) is a NIGMS-supported training program at Harvard Medical School (HMS) devoted to the deep mechanistic investigation of fundamental biological phenomena. Our primary objective is to prepare a talented and diverse group students for robust and independent careers in rigorous scientific discovery. However, the future success of our trainees and their long-term professional impact will rely on the various mentoring relationships, role models, and peer networks that support them during and after their training here. The quality of mentorship not only propels our students’ careers, but also strengthens the national culture of STEM training. HMS and the Harvard Graduate School of Arts and Sciences (GSAS) are actively collaborating to train our faculty preceptors to better meet the mentoring needs of our graduate trainees. By September 2021, over 50% of the preceptors on this grant will have participated in our mentorship program, based on the CIMER “Entering Mentoring” curriculum and other resources (e.g. NRMN); and the remaining faculty should have participated by the end of the current funding cycle in 2022. Thus, we anticipate a time when our thesis advisors have been introduced to new evidence-based benchmarks in mentorship and supporting diversity, equity, inclusion and belonging within our research community. We propose to expand upon these efforts in two ways. First, we propose to refine and disseminate curricula and pedagogical tools that faculty can employ to mentor trainees through the acquisition of peer mentoring skills, given the capacity of trainees to amplify faculty efforts to cultivate a positive culture of mentorship in their labs and communities. The past year and pandemic highlight the need of our trainees for more extensive networks of mentoring support. Second, we propose to develop, expand and promote a soon-to-be-launched open access online platform Career CogCity, which will connect faculty to the myriad resources continuously being developed to support graduate student professional development – building on our momentum to better prepare them for mentorship roles by providing resources for them to deepen conversations around individual development planning, skills acquisition, career exploration and professional development. Integral to these new training resources, we will also collect data on the impact of faculty and peer mentoring. All these efforts simultaneously serve as training resources for the administrators who manage our graduate programs, and importantly deliver a transgenerational benefit of better equipping our graduate trainees to serve as mentors and teachers during graduate school and to translate this benefit as the next generation of mentors and leaders in their professional lives.