Abstract: When trying to coax interesting quantum behavior out of a system, we normally view dissipation as a nuisance whose effects should be minimized as much as possible. In this talk, I’ll discuss a powerful and seemingly paradoxical approach where dissipation is deliberately harnessed to prepare interesting quantum states. The focus will be on quantum optomechanical systems, where the motion of a ​“large” mechanical resonator interacts strongly with light via radiation pressure forces. After an introduction to this interdisciplinary field, I’ll discuss theory from my group showing how dissipation engineering can be used to stabilize entangled states of mechanical motion. These ideas have been recently implemented experimentally to prepare nonclassical squeezed and entangled states of nanogram-scale mechanical resonators, with the relevant dissipation produced by microwave photons in a superconducting quantum circuit.