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Those on the front lines of Covid-19 care have been working impossibly long hours. Many have taken on new tasks and roles for which they have had no formal training. They have had to cope with emotionally devastating failures and face unprecedented levels of uncertainty. What health care providers have been enduring, albeit heroically, is not sustainable. They have made it work because they have had no choice. But at some point, exhaustion will overwhelm duty. Too many health care workers’ own health will suffer, leaving insufficient numbers in place to carry on. And now comes a new challenge: With their numbers of Covid-19 patients falling, hospitals now have to figure out how to resume elective procedures and continue to care for Covid-19 patients. It’s time to invent new ways. A central business concept — the S-curve — can help.