San Diego is well-known for its STEM-rich community. The San Diego Ecosystem will mobilize new and existing stakeholders to collaborate across sectors so that youth will experience connected STEM learning. We will capitalize on the strong foundation that we have built throughout the community, strengthen our efforts, and build our momentum. The partners in San Diego Ecosystem will work collaboratively to strengthen our STEM network, connect discrete STEM learning networks, map STEM assets in the San Diego Region, and share and implement the previously developed STEM Quality Criteria Rubric.