Civilizational Collapse is the process by which a large complex social organization breaks down and becomes incapable of performing its usual functions. It has occurred many times in history in specific regions, and some hypothesize that if it happened now it would dramatically affect almost all humans due to the interconnected nature of the global economy. Possible causes include severe natural or bioengineered pandemics, nuclear war and the following nuclear winter, or fragility and cascading systems failure.