Adaptation level: the point at which particular levels of competence and environment press are in balance. Competence: the theoretical upper limit of a person"s capacity to function. Environmental press: the the varying demands placed on a person by the environment. Congruence model: the notion that people need to find the environment in which they fit and that meets their needs best. Mechanisms: variables that can affect expression of competence. Outcomes: primarily physical and psychological well-being, the basic components of successful aging. There are four aspects to this approach: physical, architectural, organizational and administrative, supportive. Enables us to measure and examine separate dimensions of person-environment interaction independently. Decision to enter nursing home usually not usually made by individual. Overly helpful may harm patient making them more dependant than they need to be. Primary prevention: any intervention that prevents a disease or condition from occurring.