Distributed fiber optic strain sensing has recently received much attention for its ability tomeasure far-field rock deformation and monitor hydraulic fracture propagation during multistage fracturing treatments. This emerging technology has some unique features (i.e. spatial continuity, high resolution, and large geographical extension) that make it a promising candidate for fracture geometry characterization.In this presentation, the state-of-the-art of this technique and the principles ofstrain response measurements. Following that, leading-edge work will be introduced toquantitatively interpret field measured data in both vertical and horizontal monitoring wells.The presentation will be concluded with a field case study in an unconventional oil reservoir toillustrate the workflow of quantitative data interpretation. Fracture Properties that can beobtained from this emerging technology will be emphasized. The results of the study willhighlight the value of the strain dataset and advance our understanding of complex fracture geometry created during multi-stage fracturing treatments in unconventional reservoirs.Key takeaway from this presentation: Detailed far-field information about hydraulic fracture geometry can be obtained from the distributed fiber optic strain sensing technique.Quantitative data interpretation can substantially enhance the value of data acquired by this technique and facilitate the technique to be a routine procedure for evaluating completion quality and efficiency.