John Holland’s theory of personality types was first published in the 1950’s. After that, it has been revised and updated 6 times. He focused on the relationship between the person, the environment as well as the behavior that resulted from this environment. He distinguishes between 6 basic personality types that fits certain career environments.   

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Realistic personality (R) 

Individuals who are physically strong, deal with problems in a more practical way and who are not very socially competent. These individuals are interested in outdoor activities and also activities that require handiness.  

Practical careers which would fit these individuals best: engineering, technical, farming, construction, etc.   

Investigative personality (I)

 Individuals who are thinkers and not doers.  They have a more intellectual and theoretical orientation. These individuals often avoids interpersonal contact as they are much more interested in investigating certain phenomena. 

Intellectually orientated careers choices: mathematics, science, archaeologist, etc. 

Social personality (S)

These individuals are very competent in interpersonal relationships and verbal activities and they have a helping orientation.  

Human-oriented careers choices: nursing, social work, psychology, teaching, etc.   

Conventional personality (C) 

These individuals prefers to work with numbers or to perform clerical tasks rather that with ideas and people.  

Well-structured working careers: secretarial work, accountancy, bookkeeping, etc.   

Enterprising personality (E) 

These individuals are very competent verbally and they are very outgoing and likable. 

Careers: management, sales, politics, etc.   

Artistic personality (A) 

These individuals have a very creative orientation and they’re able to relate to the world through art. They tend to express themselves through ideas and materials in a novel way. They avoid conventional situations and do not like to conform. 

Artistic careers: musician, photographer, actor, artist, etc.   

Holland does, however, acknowledge that individual personalities differ and that personality is more complex than the description of the 6 types of personalities above. Most individuals cannot be described as only one personality type, but specific characteristics are dominant. A woman can, for example, be predominantly artistic but she may also be enterprising and social. Therefore, Holland established a code system to indicate the person’s personality characteristic. The woman (from the example above) has characteristics that could be coded as AES. 

Additionally, Holland was of the opinion that both career and non-career behavior result from an interaction between a person’s specific personality pattern and the environment in which he/she functions. He proposes a hexagonal model to illustrate the predictability of behavior.   

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One could then expect that the adjacent types (e.g. artistic and social) have more in common, while the opposites have less in common (e.g. artistic and conventional). The degree of correspondence between the personality type and environment may be determined and also the degree to which the individual has well-defined goals and a clear picture of his or her talents and interests.    

An all-in-one explanation:

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