Sustainability challenges in socio-ecological systems (SES) are inherently multiscale phenomena, as changes at the global level can result from socio-ecological processes operating at different spatial and temporal scales. In the last decade, increasing geopolitical tensions and (sometimes violent) conflicts suggest that the world may be moving towards multipolar, ‘divided world’ scenarios. In any case, any local SES is embedded in these global trajectories, pushing them while simultaneously being pushed by events and tendencies at other scales. Analysis and models of SES therefore need to incorporate multiple scales, which requires robust methods for transferring information between scales. Due to the increasing global connectivity of SES, upscaling – that is, increasing the extent or decreasing the resolution of a study – is becoming ever more important. While relationships between scales have received much attention in ecology, hydrology and climate science, less attention has been given to this challenge in analysing and modelling of SES, which therefore emerges as a pressing challenge. In this session, we will explore how eLTER can advance the analysis of upscaling phenomena in socio-ecological systems. Questions discussed in this session will focus on the requirements for integrating place-based research in LTSER Platforms and national to continental approaches in social ecology.