The pressure within latex balloons remains constant despite the balloons being inflated to more than 40 times their initial volume. We used this property to enable improved tracheal cuff pressure control. A latex balloon with an initial volume of 5 ml was connected via a vinyl duct attached with a roller clamp and three-way stopcock to a standard tracheal tube cuff. The 5 ml latex balloon was then inflated with 250 ml of air. The pressure within the tracheal tube cuff was monitored throughout anaesthesia with the inflated latex balloon acting as a pressure controller. Throat symptoms were recorded on the first four postoperative days. The controller kept the tracheal tube cuff pressures constant, and reduced the incidence of postoperative throat symptoms. Variations in cuff pressures with and without the controller were investigated in an altitude chamber to simulate flight. In the altitude chamber, cuff pressure reached over 200 cmH2O at 10 000 feet without the controller, whereas such variations were practically eliminated when the controller was used.