An irrigator-aspirator cannula (Stewart system) that may be assembled from common operating room supplies is described for use during operative laparoscopy. The unit consists of a disposable three-way stopcock inserted into a standard 5-mm suction probe. One stopcock port is connected to an irrigation fluid source and pressurized with an inflatable cuff; the other stopcock port is attached to wall suction. Flow rates were determined comparing two types of influx tubing, two different heights of the fluid source, and a range of inflatable cuff pressures. The flow rate of this system with urologic irrigation tubing at pressures of 150 mmHg was comparable to that of a commercially available irrigator-aspirator system. The instrument has been used in 15 routine and emergency operative laparoscopy cases and provides adequate aquadissection, rapid and easy maintenance of a clean operative field, smoke evacuation during laser vaporization, and atraumatic suction traction of tissues.