British citizens between the ages of 18 and 32 can join the U.K. Special Forces Reserve with no prior British Military experience. The maximum age for those with previous British Military experience is 34. Those that wish to become part of the U.K. Special Forces Reserve must pass a selection test and commit to training that is far more difficult than the training for other British Army roles.
The number of soldiers who can succeed in the special forces is limited because the physical and mental demands are very strenuous. Those who succeed in the British Special Forces have above-average physical and mental toughness, a high degree of self confidence and the ability to operate independently or as part of a small, elite unit. Members of the special forces must be willing to deploy overseas and face hostile environments while frequently being isolated. The support staff of the U.K. Special Forces Reserve do not need to pass the selection test, though they are required to maintain fitness standards. Support staff include medical personnel, chefs and vehicle mechanics.
To join the British Army, candidates must fill out a recruitment application and meet with a career adviser who will assist them in choosing an appropriate job. They must also pass physical and mental aptitude tests administered over a two-day period.