This is a worldwide project to further explore the various families with the surname of Keefer/Kiefer/Kieffer/Keffer, Keifer, Keiffer, Kueffer, the English equivalent of Cooper and like variations. The project was initially based on the male y chromosome 12 marker test for all males with the Keefer surname, but tests with at least 37 markers will have better results. Female researchers are urged to encourage any male family members to participate in the project.