Definition extracted with permission from Simon, Fritz, et al, Family Process, Inc.:[amazon 0961551909 inline]
A system is able to change in two ways: (1) Individual parameters change in a continuous manner but the structure of the system does not alter; this is known as "first-order change." (2) The system changes qualitatively and in a discontinuous manner; this is known as "second-order change." This second type of change is systems occurs with "changes in the body of rules governing their structure or internal order" (Watzlawick, Weakland, & Fisch, 1974). Second-order change is change of change.