A dual pump irrigation/aspiration pump system capable of operating in a plurality of different modes suitable for a variety of different endoscopic surgical procedures. The system monitors actual or calculated intra-articular pressure and adjusts flow to maintain surgeon requested pressure at the surgical site while controlling outflow. The irrigation/aspiration pump system has an inflow pump and tubing dedicated to communicating fluid to the surgical work site and an outflow pump and tubing dedicated to removing fluid from the work site at a controlled rate. The system further has different size inflow and outflow pumps and tubing cassettes, means for altering the outflow fluid flow rate to accommodate a surgical tool and a means for declogging the surgical tool in the event of blockage. In a preferred embodiment a pressure control system provides inferred pressure information representative of the pressure at the work site.