Creating a statewide STEM Ecosystem seems like a big job… and it is! Because of a growing need for long-term sustainability and in response to COVID-19, in 2020 Pennsylvania’s 8 formal Ecosystems (and several other networks) joined together to form the Pennsylvania Statewide STEM Ecosystem (PSSE). In partnership with the Pennsylvania Department of Education, we have developed a vision, mission, and strategic planning process; have identified short-term and long-term goals; have crafted a governance and communication infrastructure; have launched policy initiatives, hold bi-monthly STEM stakeholder webinars; and now have a distribution list of over 750 members. individuals. This hands-on session will review our process, products, successes, and lessons learned. We will also introduce the new TIES/PSSE Ecospheres initiative – though which others can create similar groups of like-minded Ecosystems.