Groundwater-surface water interfaces are crucial for the continuity of aquifer-river and aquifer-lake systems. These interfaces include various interconnected zones such as hyporheic zones, benthic zones, riparian corridors, and lake sediments, where bidirectional interactions between surface water and aquifer occur. Current research focuses on the effects of water exchange on the transport and transformation of nutrients, microplastics, and pollutants. It also addresses the control of heat, oxygen, and organic matter budgets available to microorganisms and macroinvertebrates in sediments. However, further investigation is needed to establish a comprehensive understanding of the physical, biogeochemical, and ecological processes occurring at groundwater-surface water interfaces, and their implications for fluvial ecology and limnology. Furthermore, it is essential to consider how exchange fluxes respond to environmental and climate factors at different spatial and temporal scales, such as river channels, alluvial aquifers, and regional groundwater flow. Upscaling and downscaling of a general conceptual framework, as well as enhancing process comprehension, are identified as the most significant challenges in this field of research. We invite contributions that focus on the development and application of novel experimental methods for studying physical, biogeochemical, and ecological conditions at the groundwater-surface water interface in rivers, lakes, riparian zones, and wetlands. One of our main interests lies in investigating the role of hyporheic processes in the retention and natural attenuation of nutrients and pollutants, and their influence on surface and groundwater quality. Additionally, we encourage research involving hydrological, biogeochemical, and ecological modeling approaches (e.g. transient storage models, coupled groundwater-surface water models, etc.). Finally, we welcome presentations that investigate the impact of groundwater-surface water interactions on management and risk assessment in view of the European Water Framework Directive.