Ecosystems are groups of independent firms linked through non-generic complementarities that work together to create a customer value proposition. Given the tentative consensus on the definition of ecosystems, research is now shifting to studying an interplay between ecosystem structure and performance. As a field, we wish to know where firms’ positions in ecosystems and interdependencies among firms, which underpin ecosystems in the first place, could come from. This symposium unites papers from some of the leading scholars in this emerging field that take a dynamic perspective of how various types of actors (e.g., orchestrators, complementors, component producers, government, and university research centres) shape ecosystem structure and affect firms’ performance. We will begin with looking at how ecosystem orchestrators overcome challenges associated with collaborations and investments in innovative start-ups, then take a graph theoretic approach to map patterns of interdependencies that drive acquisition choices by ecosystem members, and subsequently examine the emergence of an ecosystem from a technological discovery to commercialization. Next, we explore strategies complementors deploy as they join platform-based ecosystems and take a closer look at value co-creation and capture between a platform owner and complementors. The (brief) presentations are followed by extensive discussion, between presenters and co-authors, and by moderated Q&A with the audience. Our collective aim is to improve our understanding of the temporal dynamics shaping ecosystem structure and their link to ecosystems’ and firms’ performance. Orchestrating an Ecosystem: A Temporal Study of Ex-Ante Intentions, Ex-post Actions and Performance Presenter: Sukhun Kang; London Business School Presenter: Gary Dushnitsky; London Business School Ecosystem Interdependencies as Drivers of Acquisitions Presenter: Natalie Jane Burford; INSEAD Presenter: Andrew V. Shipilov; INSEAD Presenter: Nathan Furr; INSEAD The Emergence of Innovation Ecosystems: Organizational Mutation and Coopetition in Nanotechnology Presenter: Israel Drori; - Presenter: Dovev Lavie; Bocconi U. Playing with Platforms: A Complementor Strategy Perspective Presenter: Elizabeth J. Altman; U. of Massachusetts, Lowell Presenter: Mary Tripsas; U. of California, Santa Barbara Value Co-Creation and Capture in Platform Markets: Evidence from a Creative Industry Presenter: Carmelo Cennamo; Copenhagen Business School Presenter: Grace Gu; Boston College Presenter: Feng Zhu; Harvard U.