The measurement of foliation inflection/intersection axes (FIA) preserved within porphyroblasts, have revealed much more extensive histories of deformation and metamorphism than previously recognized during the study of orogenesis. FIA data have been applied to solving many geological problems. This paper main focused on the significance of FIA data, the measurement of FIA and how it can be applied to solving geological problems. Take Arkansas River region, USA for example to interpret the application of FIA measurements in regional and detail study of deformation process during orogenesis.