The Johari window is a technique created in 1955 by two American psychologists, Joseph Luft (1916–2014) and Harrington Ingham (1914–1995), used to help people better understand their relationship with self and others. It is used primarily in self-help groups and corporate settings as a heuristic exercise.
When performing the exercise, subjects are given a list of 55 adjectives and pick five or six that they feel describe their own personality. Peers of the subject are then given the same list, and each pick five or six adjectives that describe the subject. These adjectives are then mapped onto a grid.
Charles Handy calls this concept the Johari House with four rooms. Room 1 is the part of ourselves that we see and others see. Room 2 is the aspects that others see but we are not aware of. Room 4 is the most mysterious room in that the unconscious or subconscious part of us is seen by neither ourselves nor others. Room 3 is our private space, which we know but keep from others.
Open or Arena: Adjectives that are selected by both the participant and his or her peers are placed into the Open or Arena quadrant. This quadrant represents traits of the subjects that both they and their peers are aware of.
Hidden or Façade: Adjectives selected only by subjects, but not by any of their peers, are placed into the Hidden or Façade quadrant, representing information about them their peers are unaware of. It is then up to the subject to disclose this information or not.
Blind : Adjectives that are not selected by subjects but only by their peers are placed into the Blind Spot quadrant. These represent information that the subject is not aware of, but others are, and they can decide whether and how to inform the individual about these "blind spots".
Unknown: Adjectives that were not selected by either subjects or their peers remain in the Unknown quadrant, representing the participant's behaviors or motives that were not recognized by anyone participating. This may be because they do not apply or because there is collective ignorance of the existence of these traits.
A Johari window consists of the following 55 adjectives used as possible descriptions of the participant. 
One therapeutic target may be the expansion of the Open (Arena) square at the expense of both the Unknown square and the Blind Spot square, resulting in greater knowledge of oneself, while voluntary disclosure of Private square may result in greater interpersonal intimacy and friendship.
- Luft, J.; Ingham, H. (1955). "The Johari window, a graphic model of interpersonal awareness". Proceedings of the western training laboratory in group development (Los Angeles: UCLA).
- Luft, Joseph (1969). Of Human Interaction. Palo Alto, CA: National Press. p. 177.
- http://kevan.org/johari. Retrieved 24 November 2014. Missing or empty
- P. Perry, Couch Fiction (2010) p. 123-4
- Luft, Joseph (1972). Einfuhrung in die Gruppendynamik. Klett.
- Hase, Steward; Alan Davies; Bob Dick (1999). The Johari Window and the Dark Side of Organisations. Southern Cross University.
- Handy, Charles (2000). 21 Ideas for Managers. San Francisco: Jossey-Bass. ISBN 0-14-027510-X.
- Johari Window : Peeping into Oneself
- Noogenesis article on the Johari Window, Examples of window-altering actions; game theory aspects.
- Online Johari Window tool, by Kevan Davis