Abstract figure legend The carotid body has been linked with the development of hypertension and heart failure in animals and humans. This review explores mechanisms of carotid body sensitisation across disease models. We ask whether these mechanisms are common or unique to distinct cardiovascular diseases; such knowledge could inform clinical treatment strategies. We propose that carotid body sensitivity increases progressively from health to hypertension and is maximal in heart failure and that there are both shared and distinct sensitisation mechanisms. This sensitisation is followed by an increase in systemic sympathetic outflow. It remains unknown whether the sensitised carotid body drives sympathetic overactivity or vice versa.image