The context drives behavior

The Association for Contextual Behavioral Science defines contextualism as "a world view in which an event is interpreted as an ongoing act inseparable from its current and historical context and in which a radically functional approach to truth and meaning is adopted". An individual's understanding of an event includes a "sense of the purpose, meaning, and function of the event," all depending on past events or the historical context of the present event (ACBS, 2007, p. 1).

In other words, individual behavior depends on the continuously changing context of society and history. This means that every behavior is a historic event that results in change (Lerner, 2002, p. 71). Contextualism attempts to understand what a person is doing and what meanings ascribe to his or her actions in relation to surrounding events (Goldhaber, 2000).

The contextualist model of human development assumes constant change and "embeddedness" (Lerner, 2002). Constant change means nothing is uniform; "change is a given" (Lerner, 2002, p. 72), and the only constant is change. "Embeddedness" means that all levels of analysis are dynamically interrelated. The constantly changing organism exists in a constantly changing environment. The dynamic interaction between organisms and the environment causes changes in both the organism and the environment.