The treeline ecotone is a complex system comprised of multiple interactions that serves as a potential bellweather for responses of marginal ecosystems to climate change. For this reason, treeline ecotones have served as a focal system for disciplines across the natural sciences, globally. Recent significant advances in treeline ecotone research have influenced climate change research beyond the treeline ecotone, but further advances will rely on cross-disciplinary integration of theoretical and methodological approaches. This session brings together ecologists, ecosystem scientists, geographers, ecophysiologists, and hydrologists to solidify our understanding of treeline dynamics across domains of time and space. The speakers will provide a dynamic overview of their research that will link across disciplines to provide a holistic understanding to treeline ecotone research. By bringing together scientists working on a similar system from divergent backgrounds, we provide the opportunity for cross-disciplinary communication that, with guided post-seminar questions, will bridge a path forward. The session will be divided into three sections. A single talk will introduce the breadth of treeline research and applications beyond the treeline. The seven "Foundation" talks, will highlight significant advances in ecology, geography, ecophysiology, ecosystem science, and hydrology. Two speakers will identify paths forward in the “Ways Forward” section. The first speaker will present a case study on an international collaborative treeline experiment. The second speaker will summarize the session and explain how the North American Treeline Network (NATN) provides a path forward by bringing together scientists across disciplines to prioritize research initiatives and build collaborations.