Abstract: A cushioning means for an intensifier for delivering ultra high pressure water to the cutting head of a water jet cutting apparatus. The intensifier has a power piston and cylinder assembly connected to secondary fluid pumping piston members which extend into pumping chambers located at opposite ends of the hydraulic piston and cylinder assembly, and in a common housing. Inlet poppet valves located in the pumping chambers control the flow of water from inlet passage into the pumping chambers while outlet poppet valves allow ultra high pressure water to be pumped out of the pumping chamber into an accumulator fluidly connected to the cutting head. Hydraulic fluid under pressure is sequentially directed to opposite ends of the piston and cylinder assembly, with the piston and cylinder assembly being provided with cushioning means to assist in smooth deceleration of the piston during each stroke or cycle.