The story of the development of the Myers-Briggs Type Indicator® (MBTI®) instrument, as captured by Wright Saunders (1991), states that in 1929 Katharine Briggs read a review of Jung's Psychological Types (Jung, 1923/1971), which at that stage had just been translated into English. She became a Jung enthusiast and spent the next 20 years studying his work and checking his theories against her own observations. She always had a strong and intuitive interest in children. It was this interest in the development and individuality of children, as well as in aspects of effective parenting, that led to her discovery and appreciation of Jung. She became convinced that what Jung had to say was of value to all people in understanding themselves and others.

Katharine shared her convictions with her daughter, Isabel Briggs Myers, and during World War II (1939–1945) the two women started developing an indicator that would enable people to gain access to their preferred Jungian type. They felt that if people could be placed in jobs which they would find satisfying, and in which they could rely on their gifts, it would not only give them greater work satisfaction but would also contribute to their increased productivity. Neither of these women were psychologists, nor had they even taken a course in psychology, but their own research had convinced them that Jung's theory was sound and practical (Wright Saunders, 1991).

Isabel formulated indicator items, and tried them out on friends and family. This was the beginning of a thorough and lengthy search for appropriate items that would more accurately enable the identification of a true type and the compilation of the Type Indicator (Wright Saunders, 1991). Over the years Isabel worked with large samples in order to validate the Indicator's use, including 15 000 nurses and 5 000 doctors. According to Van der Hoop (1970, cited in De Beer, 1997), a particular contribution that Briggs and Myers made to Jung's theory was the development of the Judging-Perceiving scale. Although Jung had mentioned that he observed differences between individuals relating to this preferred attitude to life, the Myers-Briggs team had to formulate and develop a scale to measure this attitude.