Under conditions of true complexity - where the knowledge required exceeds that of any individual and unpredictability reigns - efforts to dictate every step from the center will fail. People need room to act and adapt. Yet they cannot succeed as isolated individuals, either - that is anarchy. Instead, they require a seemingly contradictory mix of freedom and expectation - expectation to coordinate, for example, and also to measure progress.

Checklists... made the reliable management of complexity a routine. That routine requires balancing a number of virtues: freedom and discipline, craft and protocol, specialized ability and group collaboration. And for checklists to help achieve that balance, they have to take two almost opposing forms. They supply a set of checks to ensure the stupid but critical stuff is not overlooked, and they supply another set of checks to ensure people talk and coordinate and accept responsibility while nonetheless being left the power to manage the nuances and unpredictability the best they know how.