Two studies investigate subjective wellbeing (SWB) homeostasis. The first investigates the contribution of job satisfaction (JS) and partner satisfaction (PS) to the homeostatic defense of SWB. The extant model of homeostasis does not include either variable. The second study investigates the relationship between Homeostatically Protected Mood (HPMood) and other factors involved in the homeostatic model. It has been proposed that HPMood is the basic, biologically determined, positive mood that saturates SWB and other related variables, and forms the basis of the SWB set-point. Thus, if HPMood is an individual difference and it perfuses other homeostatic variables, then HPMood should be responsible for much of the shared variance between such variables. Two comparative samples are involved. One is a group of 171 Hong Kong Chinese recruited through convenience sampling. The other is a group of 343 Australians recruited via a general population survey. Results indicate that both JS and PS predict significant variance in Global Life Satisfaction beyond the existing factors in the homeostatic model. It is also found that, after controlling for the effect of HPMood, the strength of correlations between SWB and other homeostatic variables is significantly diminished. The implications of these findings are discussed.