Mountain rescue refers to search and rescue activities that occur in a mountainous environment, although the term is sometimes also used to apply to search and rescue in other wilderness environments. This tends to include mountains with technical rope access issues, snow, avalanches, ice, crevasses, glaciers, alpine environments and high altitudes. The difficult and remote nature of the terrain in which mountain rescue often occurs has resulted in the development of a number of specific pieces of equipment and techniques. Helicopters are often used to quickly extract casualties, and search dogs may be deployed to find a casualty.
Mountain rescue services may be paid professionals or volunteer professionals. Paid rescue services are more likely to exist in places with a high demand such as the Alps, national parks with mountain terrain and many ski resorts. However, the labor-intensive and occasional nature of mountain rescue, along with the specific techniques and local knowledge required for some environments, means that mountain rescue is often undertaken by voluntary teams. These are frequently made up of local climbers and guides. Often paid rescue services may work in co-operation with voluntary services. For instance, a paid helicopter rescue team may work with a volunteer mountain rescue team on the ground. Mountain rescue is often free, although in some parts of the world rescue organizations may charge for their services. But there are also exceptions, e.g. Switzerland, where mountain rescue is highly expensive (some 2,000 to US$4,000) and will be charged to the patient. In more remote or less-developed parts of the world organized mountain rescue services are often negligible or non-existent.