[en] The stress imposed on the available water resources due to man's impact (exploitation, release of pollutants and agricultural practices) has resulted in depletion of the available reserves as well as deterioration of water quality in many parts of the world. Over wide areas, abstractions are exceeding current natural recharge and it is apparent from scientific studies that these water resources are being mined, especially in arid and semi-arid areas. Sustainable development and management of those water resources needs long term monitoring records to understand the changes and dynamic responses due to the exploitation. These proceedings provide a synthesis of a series of hydrochemical, isotope and geohydrological data sets which will be used for quantitative assessment of the long term dynamic response of the groundwater system. The results show that both stable and radioactive isotopes are excellent tools for characterizing and understanding aquifer systems that are undergoing long term exploitation. Specific outcomes include establishment of methodologies for monitoring and predicting changes in water quality and quantity that will lead to improved water resources management. This publication is a summary of the results achieved during the coordinated research project (CRP) and the various studies performed by the participating institutions are presented as individual presentations. The overall achievements are presented as an executive summary, and the detailed findings are presented in each contribution. These results were presented in the final coordination meeting held in Vienna, 12-16 May 2003. The results obtained from this CRP will be used to improve the predictions of future behaviour of groundwater resources in response to exploitation. The scientific component of this CRP will be a valuable source of information for isotope hydrologists involved in isotope field applications and a useful guide for groundwater managers involved in groundwater resources programmes