An electrosurgical system is capable of selectively varying the power applied to an electrosurgical probe, without interruption or discontinuity, in a variable mode or providing a constant coagulation power value to the probe. In a fixed mode, power to the electrosurgical probe must be discontinued to change the power level output by the probe. A single controller is capable of operating the probe in the variable mode and the fixed mode. The controller includes an actuator for stopping the cutting operation and then switching to a constant coagulation output during either of the variable mode or the fixed mode. The controller of the system may selectively control a separate surgical tool.