Although mentoring interventions have helped to advance diversity, equity, and inclusion (DEI) goals within STEM fields, even the most efficacious programs can be undermined without intentional cultivation of the broader mentoring ecosystem. This study examines participants from eight campus teams that engaged in a multi-session process of learning about a STEM-mentoring ecosystem (STEM-ME) framework, learning particular terminology, including 'champions' and 'stewards' within the system (i.e. who is advocating for and resourcing mentoring, respectively), and tools to inventory, map and analyze their mentoring ecosystem. Qualitative research, guided by interpretive phenomenological analysis, focused on (a) completed inventory tools, (b) visual mapping exercises, and (c) field notes from meeting sessions. The results indicate that the STEM-ME framework and new terminology facilitated important insights into possible synergies within the system. The opportunity to visualize an institutional ecosystem for concentrations of and gaps in activity helped to identify potential vulnerabilities and places to invest.