Hydraulically induced fractures usually initiate at very small (microscopic) length scales and then merge to larger (macroscopic) crack discontinuities. The goal of the project is to resolve this inherent characteristic through the development of computational scale-bridging techniques for hydraulic fracturing of porous media. The project is divided in three steps: (i) Development of a general basis for the homogenization of porous media; (ii) Incorporation of a fracture phase-field at micro-scale; (iii) Incorporation of elastic-plastic effects at micro-level. The result will be a new quality in the modelling of hydraulic fracturing across length scales.