This paper presents the results of a series of experiments attempting to determine the methods of selection, preparation, and use of turtle shell and cattle bone materials for divination during the Late Shang period. Specific topics covered include selection, preparation, drilling of burning-pits and application of heat, the reading by the diviners of the resulting cracks, the function of the historian's first writing the divination data on the bone before it was inscribed, the reason the cracks and divination data were carved into the bone and why pigment was applied to them, the actual inscription-carving technique, the result of experiments on methods of softening bones and shells, and preparing bronze and jade inscription-carving knives. I have examined excavation reports and earlier publications by scholars in the field and compared them with my own results in order to gain more complete understanding of the actual process of Late Shang oracle-bone divination. In the course of carrying out these experiments, I have made a number of discoveries which I hope may fill in some of the gaps that still exist in oraclebone studies after eighty-three years.