The board is based at Leighton House, Westbury in Wiltshire, England in a dedicated camp.

AOSB is an equivalent of the Navy's Admiralty Interview Board and the Officer and Aircrew Selection Centre of the Royal Air Force.

[2] Applicants for the British Army undergo initial suitability assessments, through computer-based tests and interviews, along a number of routes.

All officer candidates will be required to attend AOSB at a point determined by the type of entry.

Candidates will usually have undertaken insight or familiarisation visits to appropriate units prior to attendance at the board.

After attending AOSB briefing, candidates will be assigned a category based on the evidence available to the assessors.

This will be: This is a four-day selection event that consists of a number of different but inter-linked intellectual, physical, mental and aptitude tests.

[4] The Boards normally run from Tuesday until Friday but a small number each year take place from Thursday until Sunday.

It is known that the assessment consists of a physical fitness assessment, an individual obstacle course, two multiple-choice tests on current affairs and general knowledge (in the past a third test covered military knowledge), three interviews, a group discussion and essay on current and moral affairs, a 5-minute lecture, individual planning exercise, and both leaderless team tasks and a series of command tasks where a team member commands the rest.

[13] He employed Bristol architect Sir Frank Wills to alter and extend the house,[14] and planted trees, including a row of Araucaria araucana (Chilean pine) which still stands there today.

[13] The house was briefly used by a prep school, Victoria College, before the War Office bought the estate in 1939.

[15] In November 2016 the estimated date of disposal of the site was given as 2024, with the Selection Board due to move to Royal Military Academy Sandhurst, Berkshire.