The ecosystem services (ES) concept is an essential tool to promote interregional conservation and development, especially in landscapes where ecological, economic, and sociocultural resources are connected. Our study capitalizes on the interregional ES flow among the three countries – China, India, and Myanmar – that share the far-eastern Himalayan Landscape. We used participatory GIS mapping to visualize the ES flow from three protected areas (PAs) in the landscape, and participatory scenario analysis to understand the direction PA management could take. The service provisioning hotspots, the service beneficiary areas (SBAs), and the degraded service provisioning hotspots (dSPHs) were mapped for ES that was of high management priority. The trade-offs among the ES were analysed for the three scenarios – Nature-at-Work, Nature-People Harmony, and People-at-Work. The argument for regional cooperation was affirmed with several dSPHs lying along the border, and SBAs reaching beneficiaries beyond the PAs and one country. The performances of ES under different scenarios indicated that future management of PAs must widen conservation constituencies and capitalize on multiple benefits from PAs, essentially to maximize livelihoods benefits to communities who live in and around PAs. We recommend intra, inter-country, and regional cooperation pathways for the future sustenance of ES from PAs in the landscape.