Public and private support is growing for the idea that ecosystems can be managed to increase carbon sequestration or reduce greenhouse gas emissions. So-called Natural Climate Solutions (NCS) - including strategies like reforestation, cover cropping, and wetland restoration - are not a panacea for climate change and should only be pursued together with rapid economy-wide decarbonization. However, they are part of virtually all pathways to net-zero emissions, and they have many co-benefits for soil health, biodiversity, air and water quality. Despite active carbon sequestration and other services provided by natural ecosystems, neither the present value nor the realizable benefits of NCS are well understood or properly quantified. At regional scales, where policy decisions are often made, NCS mitigation potentials are estimated from soil and tree survey data that can miss important carbon sources and sinks within an ecosystem, and do not reveal NCS effects on local energy budgets, which may or may not be climatically beneficial depending on ecosystem type. The only truly direct observations of ecosystem-scale carbon and energy exchanges (e.g., from flux towers) have not yet been systematically assessed with respect to NCS potential, and state-of-the-art remote sensing products and land-surface models are not yet widely connected to direct measurements or used to inform NCS policy making or implementation. As a result, there is a critical mismatch between the point and tree scale data most often used to determine NCS benefits, the ecosystem and landscape scales where NCS projects are actually implemented, and the regional- to continental scales at which policy makers estimate nationally determined contributions. This session will focus on novel strategies for assessing and verifying the benefits, and unintended consequences, of NCS at scales relevant to both individual NCS projects, as well as policy-relevant regional-scale assessments. These approaches include both traditional sources of information from soil cores and biomass surveys, as well as direct ecosystem-scale measurements and related data products (e.g., flux towers, remote sensing, and process-based models) that have long been used to measure ecosystem carbon cycling, but have not yet been widely applied to NCS evaluation.