An exosystem is a level in Urie Bronfenbrenners ecological systems theory that encompasses environmental elements that greatly affect a childs development. It includes institutions and influences that are external to the individual, and yet exert a decisive influence on their psycho-social development. Unlike a microsystem, the institutions that make up the exosystem are not necessarily ones with which an individual has a close, personal, or intimate relationship. Examples of exosystem include a parents workplace, mass media, school policy, social support systems, family friends, and local government policy settings. The exosystem is the third level in Bronfenbrenners 5-tiered model of child development called the ecological systems theory. It is a community institution and setting in which children do not actually participate, but which affects them in one of their microsystems that indirectly influence the child, such as the school board and the parents workplaces/jobs, city council, etc. .