Abstract
This piece which introduces an article in this issue proposes a methodology for studying individual learning and development related to sociocultural change.1 The author argues that the mediating function of activity affords a new methodology that allows the study of sociogenetic‐ontogenetic relations without having to resort to reductionism or Cartesian dualism. The tri‐part methodology involves 1) Simulation by selecting key activities that can be constrained and arranged in sequence to model changesin society, and by that same sequence of activities, induce learning and development; 2) Heterochronicity which looks comparatively at the histories and time frames of various activities in a research site as well as the comparative histories and timeframes of particular activities and the lives of different generations of the research population in the interest of identifying periods of rapid societal change, and 3) Leading activity which is co‐determined by the point in an individual's developmental history at which she participates in the activity as well as the genetic sequence of activity categoires characteristic of that society.