The displacement, migration, and relocation of individuals and communities are likely consequences of a changing climate. There are contemporary instances of that movement as well as historical analogues that illustrate the impact climate change – both sudden and slow-onset events – may have. Further, based on projected increased severity of fast-acting and destructive coastal storms, as well as sea-level rise, droughts, and desertification, many more individuals and communities may be forced to move, with attendant impact on their livelihoods. The myriad pathways of population movement, the movement itself, as well as weaknesses or failures in related systems and services they provide, may negatively affect individual and community health. This chapter provides a survey of what climate change means for public health in the migration context, and describes how existing law supports (or fails to support) appropriately responsive interventions.