Internationally, uplands hold special mammal communities, especially those found in open landscapes above the tree-line. These ecosystems are discontinuously distributed, patchy, and vulnerable to human land-management pressures (overgrazing, burning, deforestation) as well as climate change. While many upland species are seriously endangered, uplands generally retain more complete mammal assemblages than lowlands, because variously of their remoteness, lower human population density or better protection status (e.g. as national parks and wilderness areas). Historically, they have often served as refuges for lowland species (e.g. in Britain). This has led to ideas that, in future, they may be appropriate places to consider ‘re-wilding’ – the reintroduction of extinct, often larger and charismatic, mammals with a view to re-creating something resembling the mammal community of pre-agricultural times.