A mountain leader is a military professional specialising in delivering training for, or leading, operations in high altitude or extremely low temperature environments.
The conduct of warfare in high altitude or arctic environments in the British Armed Forces is the province of 3 Commando Brigade, a formation of the Royal Marines with a number of attached army elements. The brigade conducts annual training in the northern regions of Norway and has been deployed for high altitude operations globally.
Associated with the tasking as the lead force for mountain and Arctic warfare is the existence of the trade specialisation mountain leader (ML). Each sub-unit within the brigade is complemented with at least one mountain leader who will have undergone training in the Mountain Leader Training Cadre, formerly known as the Mountain and Arctic Training Cadre.
Mountain leaders (USMC and US Army) have extensive practical experience in a variety of mountain environments in both winter and summer conditions. They have well-developed hazard evaluation and safe route finding skills over all types of mountainous terrain. Mountain leaders are best qualified to advise commanders on all aspects of mountain operations, particularly the preparation and leadership required to move units over technically difficult, hazardous, or exposed terrain. In most cases the mountain leader is the highest level of qualification and is the principle trainer for conducting mountain operations. Mountain warfare instructor experience at a mountain training center or as a member of a special operations forces (SOF) mountain team is critical to the mountain leader development. Below is a list of the additional knowledge and skills expected of mountain leaders. Depending on the specific AO, mountain leaders may need additional over-the-snow mobility skills such as snowshoeing and all-terrain skiing.
Some other countries have similar specialists for operating in cold and high altitude environment.