Moment to moment awareness of ourselves and our environment. Self reflective and central to our sense of self. Intimately connected with the process of selective attention. Psychological measures: establish correspondence between mental process and physical state, problem: cannot determine what a person is experiencing. Behavioural measures: performance of special tasks, problem: must infer state of mind. Sigmund freud proposed, the human mind consists of 3 levels of awareness. Conscious mind contains thoughts perceptions and other mental processes we are aware of. Preconscious mental events, outside awareness which can be easily recalled. Unconscious events cannot be brought into consciousness in any situation. Conscious and unconscious mental life work in harmony to process information. Controlled processing is the voluntary use of attention and conscious effort. With practice, moves from controlled to automatic. Automatic processing can be performed with little to no conscious effort. Problem: may reduce chances of finding new ways to approach problems.