The Tool for Exploratory Landscape Scenario Analyses (TELSA) is a spatially explicit, GIS-based landscape-level model for simulating terrestrial ecosystem dynamics. It helps resource managers and planners assess the consequences of alternative management scenarios at the landscape scale. TELSA can be used as a tool for landscape modelling, for adaptive management, or for any other planning process that involves different groups of experts and stakeholders who need to compare and assess the outcomes of different assumptions across space and time.