We give an overview on current investigations of the project 'Morphologic characterization of the Lena Delta using remote sensing and terrain modeling' (LEDAM). They are focused on the reconstruction of thermokarst lake and basin evolution on Kurungnakh Island in the central Lena River Delta in northeastern Siberia. Detailed field data derived during the 'Expedition Lena 2008' will be combined with ALOS data analysis to obtain comprehensive information on lake and basin morphology and discriminate factors controlling it. These findings will help to assess the future evolution of thermokarst processes in ice-rich permafrost in the context of climate change.