Every project team is different because teams differ in terms of the complexity of their qualifications and in terms of characters. The personalities, behavioral patterns or preferences within the project team have to be known so that the joint work can be controlled during the dynamic group process. It is often unpleasant to discuss these issues with others because one quickly enters a terrain in which public and private roles overlap. The so-called Johari window indicates why this is so and it also explains why it is still worth to discuss these issues with fellow team members.
 The known and the unknown
The Johari window assumes that there are two kinds of knowledge, the known one and the unknown one. Moreover, it differentiates between the private and the public role of a person. Four categories are arranged in a matrix:
Self-perception and external perception (Johari window)
|known to me||not known|
|known to others||Me as a public person||My blind spot|
|not known to others||my private secret||Not known to anyone|
 Increasing perception jointly
If team members exchange views about their personalities, strengths and peculiarities, they will receive valuable clues to what one cannot perceive with regard to oneself, but with regard to others: the blind spot.
- J. Luft, H. Ingham: The Johari Window. A graphic model for interpersonal relations, Los Angeles 1955
- The Johari window on Wikipedia