Vehicle door side intrusion prevention assembly

An anti-side intrusion assembly for a vehicle door includes a reinforcing beam. Anchoring members secured to the reinforcing beam anchor the reinforcing beam to the vehicle frame or chassis. The reinforcing beam extends across the vehicle door and is anchored to the chassis at each end. One of the anchoring members a door hinge, and the other of the anchoring member is a lug generally perpendicular to the reinforcing beam. When the door is closed, the lug extends into a recess provided in a rigid portion of the door frame or chassis. Substantial bending of the reinforcing beam upon side impact on the door is prevented by bearing the lug on the rigid sidewall of the recess.