In situ retorting of oil shale requires explosive loading, hydrofracturing and so on, to produce the increase in bed porosity necessary for a self-sustaining burn. Fundamental to this are the compressive properties of oil shale. Uniaxial testing of oil shale from the Green River formation in Wyoming indicates that the compressive strength is strongly dependent on organic content and strain rate. Data from stress and strain measurements together with Combustion Analysis data were used in multiple regression computer programs to obtain correlation between ultimate compressive stresses, strain rates, and oil shale composition. The influence of organic volume and strain rate upon the ultimate strain and Young's modulus were also investigated.