A system for delivering a flow of gas to an airway of a patient respiratory system, the system comprising: a gas flow generator configured to generate the flow of gas, wherein the gas flow generator is further configured to communicate the flow of gas to a patient circuit; at least one sensor configured to generate output signals related to at least one characteristic associated with the flow of gas; and a controller, wherein the controller comprises: a loop gain controller configured to selectively control the flow of gas from the gas flow generator via the patient circuit, according to a positive airway pressure therapy mode which targets loop gain deficiency, in response to the generated output signals, wherein the loop gain controller comprises: (a) a stability metric module configured to determine at least one ventilation stability metric descriptive of ventilation stability, which correlates to a loop gain, (b) a condition monitoring module configured to monitor ventilation characteristics of the flow of gas and to provide an output indicative of the monitored ventilation characteristics, wherein the monitored ventilation characteristics at least correspond to an occurrence of sleep disorder breathing events, (c) a loop gain decision module configured to determine a future ventilation characteristic target and plant gain target based on the determined at least one ventilation stability metric and the output from the condition monitoring module, wherein the future ventilation characteristic target and plant gain target are specific to managing ventilation stability by treating a corresponding loop gain deficiency, (d) a therapy prescription decision module configured to determine a therapy command pressure or delivery characteristic based on the determined future ventilation characteristic and plant gain targets, and (e) a pressure delivery module configured to control the gas flow generator to deliver the flow of gas at the determined therapy command pressure or delivery characteristic for a future breath to overcome the loop gain deficiency and provide ventilation stability. a gas flow generator configured to generate the flow of gas, wherein the gas flow generator is further configured to communicate the flow of gas to a patient circuit; at least one sensor configured to generate output signals related to at least one characteristic associated with the flow of gas; and a controller, wherein the controller comprises: a loop gain controller configured to selectively control the flow of gas from the gas flow generator via the patient circuit, according to a positive airway pressure therapy mode which targets loop gain deficiency, in response to the generated output signals, wherein the loop gain controller comprises: (a) a stability metric module configured to determine at least one ventilation stability metric descriptive of ventilation stability, which correlates to a loop gain, (b) a condition monitoring module configured to monitor ventilation characteristics of the flow of gas and to provide an output indicative of the monitored ventilation characteristics, wherein the monitored ventilation characteristics at least correspond to an occurrence of sleep disorder breathing events, (c) a loop gain decision module configured to determine a future ventilation characteristic target and plant gain target based on the determined at least one ventilation stability metric and the output from the condition monitoring module, wherein the future ventilation characteristic target and plant gain target are specific to managing ventilation stability by treating a corresponding loop gain deficiency, (d) a therapy prescription decision module configured to determine a therapy command pressure or delivery characteristic based on the determined future ventilation characteristic and plant gain targets, and (e) a pressure delivery module configured to control the gas flow generator to deliver the flow of gas at the determined therapy command pressure or delivery characteristic for a future breath to overcome the loop gain deficiency and provide ventilation stability. (a) a stability metric module configured to determine at least one ventilation stability metric descriptive of ventilation stability, which correlates to a loop gain, (b) a condition monitoring module configured to monitor ventilation characteristics of the flow of gas and to provide an output indicative of the monitored ventilation characteristics, wherein the monitored ventilation characteristics at least correspond to an occurrence of sleep disorder breathing events, (c) a loop gain decision module configured to determine a future ventilation characteristic target and plant gain target based on the determined at least one ventilation stability metric and the output from the condition monitoring module, wherein the future ventilation characteristic target and plant gain target are specific to managing ventilation stability by treating a corresponding loop gain deficiency, (d) a therapy prescription decision module configured to determine a therapy command pressure or delivery characteristic based on the determined future ventilation characteristic and plant gain targets, and (e) a pressure delivery module configured to control the gas flow generator to deliver the flow of gas at the determined therapy command pressure or delivery characteristic for a future breath to overcome the loop gain deficiency and provide ventilation stability.