The earliest evidence for people on the Great Plains leaves many questions unanswered, but we know enough to set the stage for the changes that occurred at the end of the Pleistocene. We have seen that it is effectively impossible for the small sample of dated early sites to tell us about the continent’s very first occupants, whether Clovis was first or not. This means that people must have been on the Plains not for a few centuries prior to 10,800 BC (12,800 cal BP), but, rather, probably for thousands of years prior to that date. This has surpassingly important implications for the human context of change on the Great Plains at the end of the Pleistocene and the beginning of the modern geologic period, the Holocene.