In infantry tactics, leapfrogging (also called The Buddy System) is a technique for advancing personnel and/or equipment on or past a target area being defended by an opposing force. This technique is taught in U.S. Army Basic Training and reinforced with all unit and advanced training throughout a soldier’s career. It can be modified for use with equipment as well as personnel.

Leapfrogging requires dividing an attacking force into at least 2 parts (for example Team A and Team B). The teams agree on a signal for role assignment; for existing units, the signal is often preset and practiced. Team A will redirect or suppress the enemy by firing munitions upon the target while Team B changes positions. When the signal is given, the teams switch roles. (Team B redirects or suppresses while Team A moves.) Before changing positions, the moving team will usually identify a location that advances them on the target, has adequate cover and line of sight to engage the target. Variations of this technique may employ more than two teams (with as few as one person) in the suppressing or moving roles. A variation may be chosen based on the size and equipment of the defending force, as well as the distance and frequency of available cover. In situations where the defending force is unaware of the attacking force, it may be possible to hold fire and conduct part or all of the movement without being observed.

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