We assessed whether the outcome of severe sepsis with or without shock in Australia and New Zealand has improved from 2000 to 2012. We found that hospital mortality decreased steadily throughout this period. The decrease was systematic and applied to all patients, including multiple subgroups. The decrease in mortality remained statistically significant after adjustments. The same improvement occurred in nonseptic patients, but such patients had lower rates of discharge to home and higher rates of discharge to rehabilitation. These findings were confirmed in sensitivity analyses stratified by hospital level, hospital size, and hospital length of stay and by using only centers that had reported data throughout the study period. In 2012 and in the absence of comorbidities and older age, the mortality rate of severe sepsis or septic shock in Australia and New Zealand was 4.6%