Archaeologists have made great strides in understanding prehistoric migration, yet they have tended to focus on only part of the continuum of human movement. In nonstate societies, individuals and groups moved frequently across social and environmental boundaries for a range of reasons. Although archaeologists are well aware of the fluid nature of social boundaries, we are only beginning to use this knowledge to understand human movement. I use ethnohistoric and ethnographic examples to show that people in nonstate societies moved frequently as a result of warfare and captive taking, processes of fission and fusion, and random demographic events typical of small-scale societies. Such movement was often hurried, sometimes coerced, and decision making could be constrained by social factors beyond migrants’ control. Illustrated with a case study from the American Southwest, I argue here that consideration of such forms of movement can significantly improve our interpretations of the past.