Lieven Claessens is working as an environmental scientist and modeler at the International Potato Center (CIP) in Nairobi, Kenya. He has extensive experience with the spatial analysis and modelling of the dynamics of soil – landscape - land use systems. He developed the LAPSUS-LS landscape process model, a spatially explicit methodology for predicting landslide hazard and quantifying associated soil redistribution (erosion-sedimentation). LAPSUS-LS forms part of the LAPSUS framework, a landscape evolution model in which different processes (water erosion by runoff, tillage erosion and landslide erosion) are simulated in the context of current and future environmental change (www.lad.wur.nl/UK/Research/LAPSUS). The LAPSUS model has been explicitly linked to methodologies addressing ecological processes and land use change to assess interactions and feedback mechanisms between landscape, land use and landcover. In addition he has experience with digital soil mapping, integrated assessments of agricultural systems and land use change modeling (www.cluemodel.nl). Current research is focusing on interactions and feedback mechanisms between bio-physical and socio-economic processes from household to watershed and regional scale levels. Within the Tradeoff Analysis framework (www.tradeoffs.nl, www.tradeoffs.oregonstate.edu), case studies are conducted in Kenya, Uganda, Ethiopia, Peru and Ecuador. Integrated assessments of the sustainability of the agricultural systems are performed with an emphasis on testing adaptation strategies in the context of environmental change.