Mountains are complex landscapes with rapid changeovers between water generation, storage, evaporation and discharge in various states, including solid, liquid and gaseous. Snow, rain, and condensation form important inputs to the system, yet their precise quantification still remains a problem at high altitudes. Whereas glaciers, permafrost, lakes and groundwater reservoirs form dynamic short and long term water stores, discharge and evapotranspiration form important fluctuating outputs. Many of these components and interlinkages are still incompletely understood. New or modified approaches need to be developed to better measure, model, predict and manage high altitude water taking into account its entire spatial heterogeneity and temporal dynamics. With increasing climatic perturbations and anthropogenic pressures, a good understanding of mountain climate and water balance is essential. The main themes that will be approached include firstly: the dynamics of the water cycle in all its states, secondly, snow re-distribution by natural and human-induced processes in the water cycle and thirdly: the coupling of hydrology and climatology in future scenarios with possible emphasis on the impacts on and of dam reservoirs. Contributions are welcome on monitoring, modelling, scenario development or management prospects in all mountain regions of the world independent of scale and geographic region.