Our reasoning was straightforward. Before anything effective could be done, the major economic and scientific powers needed a shared understanding of what was happening. Political leaders required relatively direct and frequent access to the best available analysis of emerging technologies, their risks, and their opportunities. The G20 seemed the appropriate forum: Large enough to include the countries that matter, but not so large as to be unwieldy, and not so politically narrow as to exclude essential actors such as China. A body that was too expansive would be ineffective; one defined by political affinity would defeat the purpose of seeking…