ADVANCED GUARD, the protective detachment pushed forward in advance of an army, or smaller force, moving towards the enemy. Although protective in purpose, its action is largely offensive in order to fulfil its duties. These are to gain informa tion of the position and strength of the enemy's main forces, to deny similar information to the enemy's reconnoitring troops, to brush aside his advanced detachments and so prevent delay to the march of the main body. When the advanced guard eventually comes to grips with the real strength of the enemy, it should fix him securely in order to allow its own main force to deploy and manoeuvre. Gaining time is then as vital as saving time in the earlier phase, and for this purpose the advanced guard may have to resort to attack, defence, or an alternation of both.
The role of. an advanced guard may be likened to that of an outstretched arm of a man moving in the dark. Flank guards and rear guards are variations of an advanced guard whose names explain their roles. Outposts are a protective detachment to a 'orce halted.