In 1964, John Bell published a theorem that effectively turned a metaphysical question into a physical question. He showed that no local model of reality satisfying certain common-sense conditions could possibly account for the predictions of quantum theory. The winners of this year’s Nobel Prize in physics—John Clauser, Alain Aspect, and Anton Zeilinger—experimentally verified the relevant quantum predictions, thus ruling out a whole class of common-sense models. Their technical advances also opened the door to novel quantum technologies. In this talk, after first reviewing the concept of quantum entanglement, which underlies both Bell’s theorem and the prize-winning experiments, I will describe the contributions of the three laureates and discuss the implications of their work.