Synergetics is an interdisciplinary science explaining the formation and self-organization of patterns and structures in open systems far from thermodynamic equilibrium. It is founded by Hermann Haken, inspired by the laser theory.
Self-organization requires a 'macroscopic' system, consisting of many nonlinearly interacting subsystems. Depending on the external control parameters (environment, energy-fluxes) self-organization takes place.
Order-parameter concept 
Essential in synergetics is the order-parameter concept which was originally introduced in the Ginzburg-Landau theory in order to describe phase-transitions in thermodynamics. The order parameter concept is generalized by Haken to the "enslaving-principle" saying that the dynamics of fast-relaxing (stable) modes is completely determined by the 'slow' dynamics of as a rule only a few 'order-parameters' (unstable modes). The order parameters can be interpreted as the amplitudes of the unstable modes determining the macroscopic pattern.
As a consequence, self-organization means an enormous reduction of degrees of freedom (entropy) of the system which macroscopically reveals an increase of 'order' (pattern-formation). This far-reaching macroscopic order is independent of the details of the microscopic interactions of the subsystems. This supposedly explains the self-organization of patterns in so many different systems in physics, chemistry and biology.
- H. Haken: "Synergetics, an Introduction: Nonequilibrium Phase Transitions and Self-Organization in Physics, Chemistry, and Biology", 3rd rev. enl. ed. New York: Springer-Verlag, 1983.
- H. Haken: Advanced Synergetics: Instability Hierarchies of Self-Organizing Systems and Devices. New York: Springer-Verlag, 1993.
- H. Haken: Synergetik. Springer-Verlag Berlin Heidelberg New York 1982, ISBN 3-8017-1686-4
- R. Graham, A. Wunderlin (Hrsg.): Lasers and Synergetics. Springer-Verlag Berlin Heidelberg New York 1987, ISBN 3-540-17940-2
See also 
- Homepage of the former Institute for Theoretical Physics and Synergetics (IFTPUS)
- Center for Synergetics homepage