A bet made at a 2021 birthday party helped spark research showing that measurement and feedback can rein in chaos in a quantum system. Four physicists worked out the theory during summers at the Aspen Center for Physics. Testing it on an IBM device with roughly 100 qubits, a system too large for ordinary computers to simulate, confirmed their predictions. Not every chaotic quantum system is now easy to control, since quantum computers are still delicate. Still, the authors see it as a new way to steer complex quantum systems.