The industrial plant is a Soviet structure in Command & Conquer: Red Alert 2: Yuri's Revenge which decreases the price and build time of vehicles, aircraft, ships, and Soviet and Allied ore refineries by 25%. It replaces the cloning vat as the Soviet late game structure after its move to Yuri's arsenal.
Another benefit is that because it reduces the cost of ore miners, the industrial plant also reduces the cost of ore refineries, probably because the cost reduction is applied to the miner that comes with the refinery. Slave miners do not benefit from this structure's effect if built from the construction yard, but do if they are built from the war factory.
In the event players do have more than one Industrial Plant, the effect will stack; there is no limit to this. (note that cost is an integer, not a decimal, so anything after the decimal point will be cut; no rounding, up or down, is done)