The key ingredients to resilient systems are:

• Diversity: The number of elements in the system and the number of relationships between those elements.
• Modularity: The independence of each element in the system
• Tightness of Feedbacks: How long it takes the system to respond to changes

When these three features are present, a system that is facing disruption will be better able to re-organize itself to a new stable state.

Diversity

The diversity of the various elements that comprise a system include people, businesses, institutions, infrastructure, food sources, plants and animals. Each of these elements also needs a diversity of relationships to the other elements in the system.

A Diverse System	Not Diverse

Modularity

A modular system has parts that perform distinct functions independently of the other parts.  When one part ceases to become available, the other parts are able to self-organize and adapt to the change.  The highly networked and globalized nature of modern societies mean that shocks quickly spread throughout the system.  A better approach is to modularize systems so that they have more local connections.  

A Modular System	Not Modular

Tightness of Feedback

How quickly and strongly will changes in one part of the system be felt in other parts of the system. When a module in the system fails, it provides immediate feedback to it's neighbours, who adapt to the change, which triggers a change in it's immediate neighbours, etc. The length of this feedback chain determines how tight the feedback loop is. Centralized governments and globalized economies lengthen this feedback chain, decreasing resilience and increasing the likelihood of problems not being detected in time.

Tightening feedback loops by bringing the consequences of our actions closer to home is preferable to shipping our problems overseas where we won't even notice them.

Short Feedback Loop	Long Feedback Loop