The DISC model is attributed to Dr William Moulton Marston, whose book Emotions Of Normal People (1928) first explained the model using the DISC terminology, and which also provided the descriptive words on which the commonly used DISC personality assessment systems were built. Marston didn't create an assessment tool. This was done initially by researchers at the University of Minnesota, in 1972 according to Inscape. Inscape, and others, have continued to develop, test and validate DISC assessment systems, which are marketed with gusto to the corporate and organisational development communities.
The dimensions of Behaviour and Situation feature strongly in Marston's ideas.
There are several slightly varying interpretations of this model. Here's a general outline.
DISC basic personality types model There are different interpretations of this model, based on the same underpinning structure. This presentation of the DISC model borrows from various interpretations. The colours mainly emphasise the columns - they are not part of the original DISC theory - but they also reflect the logical correlations to two of the Four Temperaments and Keirsey main types (D = Phlegmatic/Rational; I = Choleric/Idealist) and the Jungian Extravert-Introvert 'attitudes'. Other than this there is no attempt here to overlay the DISC model or personality traits directly onto any other personality model. There are overlaps and correlations between DISC and other personality systems but not a direct overlay. Logical comparisons and correlations between DISC types and the types contained in the theories of Jung, Benziger, etc, are shown lower in the grid below.
Unlike testing systems such as Myers Briggs® and Keirsey which typically match people to defined 'types', The DISC model instead presents a series of four main 'type' descriptions (titled above as Dominance, Influence, Steadiness and Compliance). The DISC testing instruments tend to identify people's dominant or preferred type and one or two supporting types from the four available, and this mixture is then represented by a graph or personality description based on the mixture of the types.
In this respect no person is exclusively just one of the four DISC types. Most people have a dominant or preferred main type, plus one or two supporting types in different degrees depending on the person and the situation. DISC systems commonly not only assess the person but also the person's mix of dominant types from different perspectives.
It is important to note again that the DISC system of personality assessment, like all personality models, provides a guide and a perspective of personality; it is not a 100% reliable or definitive measurement.