Aquatic ecosystems have formed the focus of several UNESCO research projects because of the impact on them of human activities such as intensification of agricultural activity‎,‎ erosion and sedimentation due to irrigation projects‎,‎ groundwater pollution and eutrophication‎.‎ Interfaces‎,‎ or ecotones‎,‎ between terrestrial and aquatic ecosystems were found to have an essential role in the movement of water and materials throughout the landscape‎.‎ Ecotones are zones where ecological processes are more intense and resources more diversified‎.‎ They are also zones which react quickly to human influences and changes of environmental variables‎.‎ This volume summarises the results presented at an international conference dedicated to the study of groundwater/surface water ecotones‎,‎ with contributors of international scientific reputation representing the multidisciplinary viewpoints of hydrologists‎,‎ biologists and ecologists‎.‎ It addresses areas of active research in hydrology and biology‎,‎ and is aimed towards researchers‎,‎ water resource pr‎.‎‎.‎‎.‎