Intentionality is a key constituent of human action in a world of pervasive uncertainty and provisional knowledge. Intentionality provides meaning to the action plans of the agents that interact within a socioeconomic system. Social interaction produces orders that, although more than the sum of individual actions, acquire direction imprinted by the intentional content and structure of the courses of action of the individuals and organizations that interact within the system. Although many of the consequences of interaction may be unintended and even opposite to agents' intentions, the evolution of the system is not entirely blind. Explaining why and how this can be so is the purpose of this Element.