Proceedings of a recent National Academy of Sciences colloquium.

The organizers had no difficulty in finding many examples of complexity in subjects ranging from fluid turbulence to social networks. However, an acceptable definition for self-organizing complexity is much more elusive. The governing equations (if they exist) are generally nonlinear ... A few characteristics of self-organized complexity: Frequency-Size Statistics (power law scaling); Networks; Time Series; Slider Blocks; Deterministic Chaos vs. Stochasticity.

This is clearly a field that is rapidly growing. The growth is likely to be particularly strong in the biological and social science applications.

From the table of contents:

Proteins: Paradigms of complexity
Self-organized complexity in economics and finance
Random graph models of social networks
Scaling phenomena in the Internet: Critically examining criticality