Operating in a tactical environment requires strict security due to threat force ability to attack from any direction. A common phrase to establish perimeter security during patrol halts, patrol bases, rally points and defensive perimeters is the directive to establish 360 Degree Security or simply 360 Security. 360 references the degree measurement for a complete circumference of a circle. The establishment of 360 security should be a standard operating procedure within groups to ensure all individuals know their assigned position within the perimeter and the establishment of security is automatic. To establish 360 security always describe unit positions based on clock face hour locations. During movements the direction of travel is the 12 o'clock position or when in the defense the direction of the enemy is the 12 o'clock position. For example, the picture outlines a patrol security halt with the following security positions assumed: A TM LDR occupies the 12 o'clock position; the primary compass man moves to the right seeks cover and occupies the 2 o'clock position; the primary pace man moves to the left seeks cover and occupies the 10 o'clock position; A TM marksman steps to the right and occupies the 3 o'clock position; the PL takes a knee in the center of the perimeter; B TM LDR moves to the left and occupies the 8 o'clock position; alternate compass moves to the right and occupies the 5 o'clock position; alternate pace moves to the left and occupies the 7 o'clock position; B TM marksman assumes the 6 o'clock position. If the security halt is for an extended period of time the PL and TM LDRs push the perimeter out for better dispersion and security.