Geomechanics plays an important role in the utilization of conventional or alternative energy sources and in the development of sustainable energy management. The understanding and the prediction of the mechanical behaviour of geomaterials involved in the exploitation or the storage of energy resources request robust sciences. This could be summarized as follows: · Facing the limited fossil fuel resources, the way we exploit the hydrocarbon reservoir must be optimized (eg. enhanced oil recovery, borehole stabilization, oriented borehole). · Alternative sources of energy must be promoted and developed to reduce the worldwide dependency of fossil fuel. In geothermal energy, the earth being a primary renewable heat resource, geomechanics is of paramount importance. · Energy exploitation also means waste production. The ground offers a possible host environment as a definitive solution for the storage of those wastes, providing that the interaction between waste and earth are predictable and safe. Similar concepts could be applied to CO2 sequestration. Consequently, the development of the energy sector, sustainably and in harmony with the geological environment, requires rigorous understanding and assessment of the highly coupled geomechanical response of the geo-system. The goal of the workshop is to discuss the most recent contributions of geomechanics to various fields of energy. The areas of interest are related to geomechanical application in the subsurface extraction of energy and the storage of various wastes as well as CO2. It is therefore expected to provide a comprehensive contribution, which has the potential to become reference material for engineers and scientists involved in the design and the exploitation of energy geosystems. High-quality scientific work and contributions in innovative applied-oriented technologies will be encouraged. We hope this workshop will have general appeal to everybody involved in geomechanical engineering of energy geo-systems. It includes experts, companies, contractors, installers and academic researchers facing the need for a deeper understanding of the highly coupled response of geomaterials in interaction with energy infrastructures or waste storage.