The purpose of this paper is to present a multi-scale approach for the biomechanical characterization of the human liver, spleen, lung and heart. A four step study is presented to quantify the injury mechanism, biomechanical response, and rate dependent constitutive model for each tissue. First, the CIREN and NASS databases were examined in order to determine crash characteristics for injuries for each of the four organs. From this step, the injury mechanism relative to loading directions and loading rates could be approximated. Second, whole fresh human organs were tested within 36 hours of death using multiple rates of indenter style tests up to 50% compression. Third, fresh human organs were processed into either dog-bone tension coupons or cylindrical compression coupons and tested at multiple strain rates to the point of failure within 48 hours of death. Fourth, each whole organ and tissue test was recreated using FEM with scanned geometry. An optimization routine was used to develop the best constitutive model for each organ tissue. The full test matrix consists of 860 individual experiments. The overall methodology and preliminary results of the whole body, organ, tissue and modeling are presented. It is anticipated these results will provide the foundation for human FEM tissue properties.