As the appearance of a volume like the present one attests, the growing use of the microgenetic method is in the process of transforming developmental research, focusing it on its true subject – change. Cross-sectional “snapshots” are not just limited in what they portray. More seriously, they may be misleading, since an individual's second encounter with a task may reveal an entirely different approach from a first encounter. The “dynamic assessment” over time that goes back to Vygotsky provides a more informative picture of how an individual functions. Extended over a longer time period, dynamic assessment merges with the microgenetic method. Strategies evolve with the exercise that comes from extended engagement, allowing observation of the change process – a process that presumably would take place in a similar way, although at a slower pace, in the absence of this dense experience.

In this pure form, the microgenetic method allows examination of behavior as it is reorganized simply as a consequence of its own functioning – a process we can assume is a common one in natural settings, since a great many behaviors do change in the absence of instruction or explicit feedback. In this form of the microgenetic method, which my co-workers and I began to use in the early 1980s as a means of studying mechanisms of change (Kuhn & Ho, 1980; Kuhn & Phelps, 1982), the only feedback individuals receive is that arising from their own actions.