Geodynamically active regions have been recognized to be areas of anomalous Earth degassing. Geochemical and isotope composition of gases deriving from different geodynamic settings can trace sources and chemical and physical processes, providing information about deep earth. Fluids play an important role in earthquake generation, e.g. by reducing friction between the fault blocks and/or increasing pressures at depth. Moreover, active faults may act as preferential pathways for the escape of crustal fluids towards the surface and when regional tectonic structures reach the base of the crust, may act as routes for mantle fluids. Strong relations exist among heat flow, tectonics, geothermal gradient anomalies and fluids, which are strictly connected with the ascent of magma and hot fluids. This process transfers mass and heat from the planet’s interior towards its surface and is the main source of geogenic gases towards the atmosphere. In particular, carbon plays a key role in major geodynamical processes such as mantle melting, volcanic degassing and seismicity. The amount of carbon present in the mantle affects the onset of deep melting, the geophysical properties of the mantle as well as long-term climate change when CO2 is released into the atmosphere. While CO2 is one of the major constituents in volcanic/geothermal areas, methane, dominating sedimentary low heat flow areas, is often linked to subsurface hydrocarbon reservoirs that due to tectonic discontinuities are released in the atmosphere. The quantification and the pathway recognition of the above-mentioned carbon species can also help in the estimation of the geological greenhouse gas emissions. In addition, noble gases deriving from the deep earth can provide important information about their crust or mantle origin because these gases hardly react with other materials during migration. In particular, helium is a sensitive tracer for both fluid migration and gas origin. Moreover, He isotope ratios are directly correlated with heat flow, because the latter mainly derives from the crust and mantle and therefore, the majority of the earthquake epicenters occur in zones of anomalous gradient worldwide. Moreover, radon as it escapes from tectonic faults, can be used for the geochemical prospection of the deep faults rooted in the crust. To conclude, geochemical studies on Earth degassing have clearly shown a striking correspondence between areas with active tectonics and anomalous gas emissions on various scales. This session aims to merge different geo-disciplines and bring together researchers interested in the comprehension of the degassing processes that take place in various geodynamic regimes. Contributions concerning innovative and improved sampling methods and techniques are welcome.