Only one in seven of the world’s population has ever migrated, despite the enormous gains in income possible through international and internal movement. This paper examines the evidence for different explanations given in the economics literature for this lack of movement and their implications for policy. Incorrect information about the gains to migrating, liquidity constraints that prevent poor people paying the costs of moving, and high costs of movement arising from both physical transportation costs and policy barriers all inhibit movement and offer scope for policy efforts to inform, provide credit, and lower moving costs. However, the economics literature has paid less attention to the fears people have when faced with the uncertainty of moving to a new place, and to the reasons behind the tears they shed when moving. While these tears reveal the attachment people have to particular places, this attachment is not fixed, but itself changes with migration experiences. Psychological factors such as a bias toward the status quo and the inability to picture what one is giving up by not migrating can result in people not moving, even when they would benefit from movement and are not constrained by finances or policy barriers from doing so. This suggests new avenues for policy interventions that can help individuals better visualize the opportunity costs of not moving, alleviate their uncertainties, and help shift their default behavior from not migrating.