Beam-riding guidance leads a missile to its target by means of radar or a laser beam. It is one of the simplest forms of radar or laser guidance.

The main use of this kind of system is to destroy airplanes or tanks. First, an aiming station (possibly mounted in a vehicle) in the launching area directs a narrow radar or laser beam at the enemy aircraft or tank. Then, the missile is launched and at some point after launch is "gathered" by the radar or laser beam when it flies into it. From this stage onwards, the missile attempts to keep itself inside the beam, while the aiming station keeps the beam pointing at the target. The missile, controlled by a computer inside it, "rides" the beam to the target. The aiming station can also use the radar returns of the beam bouncing off the target to track it, or it can be tracked optically or by some other means.