In the context of geothermal exploration, the geothermal fluids have particular importance. Their composition, pH, temperature, distribution, and abundance indicate the geometry of the geothermal system and determine its suitability for exploitation. Furthermore, a good characterization of the geothermal fluids is important in monitoring the response of geothermal reservoirs to production loads during the exploitation phase. These fluids can be found at natural discharge areas (e.g. hot springs) or at drilled wells. However, due to the sensitivity of the required subsequent chemical analyses, it is important that the fluid samples are collected with care following established protocols. Also, a good understanding of geochemical sciences is necessary for the choice of the analysis methods as well as a sound interpretation of the analysis results. GSE offers all or part of the following services: