‘Perfect storms in networks’ shows that the range of possible dynamics in networks is enormous. Domino effects, co-extinctions, cascading failures, breakdown avalanches, systemic failure of economic networks, congestion phenomena, epidemics, pandemics, computer viruses, viral marketing, and social spreading are all examples of ‘power storms’. The structure of networks affects their robustness. The Internet, the WWW, and most of the real-world networks are able to function normally even when a large fraction of the network is damaged, but suddenly certain small failures, or targeted attacks, bring them down completely. Highly connected nodes in heterogeneous networks play a crucial role, in both errors and attacks.