HOLLAND'S 
PERSONALITY THEORY
John Holland's theory suggests that people can be classified into 6 personality types. These basic personality types are Realistic, Investigative, Artistic, Social, Enterprising and Conventional. 

RIASEC is the easiest way to remember the 6.  Startng with Realistic and going clockwise.

Types located closer together on the hexagon have greater similarities than types located at opposite ends of the hexagon. For example, the Enterprising and Social types both value personal contact while the Realistic and Investigative types perform more independently.

Another example would be the more verbal orientation of the E, S, A types versus the more nonverbal orientation of the C, R, I types.


Five assumptions underline his theory:

1. Most people can be categorized as one of six personality types: Realistic,
Investigative, Artistic, Social, Enterprising, or Conventional.
2. There are six kinds of work environments: Realistic, Investigative, Artistic,
Social, Enterprising, and Conventional.
3. People search for environments that allow them to use their abilities and to
express their values and interests.
4. People's behavior is determined by an interaction between their personality
type and the characteristics of the environment.
5. People are usually happier and more satisfied if there is compatibility or "fit"
between their personality type (interest, abilities, and values) and their chosen
work environment.

Realistic
• LIKES: You like to work with things you can see and touch like animals, plants ,tools, or machines. 
• You prefer things that seem real rather than ideas or concepts.  You like to fix things or put things together. 
• DISLIKES: Generally avoids social activities like teaching, healing, and informing others. They prefer to deal with things rather than with ideas or with people.
• Such people usually have trouble expressing themselves in words or in communicating their feelings to others.
• SIMILAR TYPES: The two work environments that are closest to the Realistic type are Conventional and Investigative. The farthest away is the Social type.
• PERSONALITY TRAITS: Conforming, frank, persistent, practical, stable, and thrifty.
• REALISTIC OCCUPATIONS: electrician, cook, nuclear reactor technician, environmentalist, forest ranger, aeronautical engineer, truck driver, mail carrier, police officer, construction or athletics.

Investigative
• LIKES: You enjoy logical thinking and like to understand how things work.
• They like scientific and mathematical tasks and solving complex problems (enjoy vague challenges and enjoy solving abstract problems and have a great need to understand the physical world.
• Sees themselves as scholarly and lacking in leadership skills.
• DISLIKES: Generally avoids leading, selling, or persuading people. Such people and do not like highly structured situations with many rules.
• They are not particularly interested in working around other people. They frequently have unconventional values and attitudes and tend to be original and creative, especially in scientific areas
• SIMILAR TYPES: The two work environments that are closest to the Investigative type are Realistic and Artistic. The farthest away is the Enterprising type.
• PERSONALITY TRAITS: Analytical, cautious, critical, introverted, passive, rational, and reserved.
• INVESTIGATIVE OCCUPATIONS:  physician, mathematician, oceanographer, meterologist, college professor, psychologist, engineer, computer technician, x-ray technician, and architect.

Artistic
• LIKES: They enjoy art, dancing, acting, music. 
• They like to express themselves freely,  work in artistic settings and enjoy variety and creativity.
• They  prefer to work alone, need for individualistic expression, are usually less assertive about their own opinions and capabilities, and are more sensitive and emotional.
• Sees self as expressive, original, and independent.
• DISLIKES: Such people have little interest in problems that are highly structured or require gross physical strength.
• They generally avoids highly ordered or repetitive activities
• SIMILAR TYPES: The two work environments that are closest to the Artistic type are Investigative and Social. The farthest away is the Conventional type.
• PERSONALITY TRAITS: Complicated, emotional, idealistic, imaginative, introspective, intuitive, nonconforming, original, and self-expressive.
• ARTISTIC OCCUPATIONS:  advertising , fashion model, decorator, artist, music teacher, orchestra leader, entertainer, writer, editor, critic,, radio program writer, director, actor, or designer.

Social
• LIKES: They like to work with people. They are sociable, are friendly, responsible, humanistic, and concerned with the welfare of others and care about other's feelings.
• They like helping, understanding, and teaching others.
• They enjoy solving problems by talking about them.
• They usually express themselves well and get along with others; they like attention and seek situations allowing them to be at or near the center of the group
• DISLIKES: They have little interest in situations requiring physical exertion or working with machinery
• SIMILAR TYPES: The two work environments that are closest to the Social type are Artistic and Enterprising. The farthest away is the Realistic type.
• PERSONALITY TRAITS: Cooperative, friendly, generous, tactful, responsible, outgoing, helpful.
• SOCIAL OCCUPATIONS: teacher, counselor, psychologist, librarian, recreation director, social worker, housekeeper, ticket agent, hair stylist, and politician.

Enterprising
• LIKES: You like to lead others and have a great facility with words, which they put to effective use in selling, frequently they are in sales work. 
• They see themselves as energetic, enthusiastic, adventurous, self-confident, and dominant, and they prefer social tasks where they can assume leadership
• They enjoy persuading others to their own viewpoints
• You enjoy competition and like to be in control.  You are willing to be responsible for getting your work done and for supervising others.
• Values success in politics, leadership, or business
• They like power, status, and material wealth, and enjoy working in expensive settings.
• DISLIKES: They are impatient with precise work or work involving long periods of intellectual effort and generally avoids activities that require careful observation and scientific, analytical thinking
• SIMILAR TYPES: The two work environments that are closest to the Enterprising type are Social and Conventional. The furthest away is the Investigative type.
• PERSONALITY TRAITS: Adventurous, argumentative, independent, impulsive, pleasure seeking, sociable, dominant, and persuasive.
• ENTERPRISING OCCUPATIONS: banker, florist, postmaster, apartment manager, restaurant owner, sales clerk, sporting goods salesperson, travel guide, journalist, lawyer, flight attendant, labor arbitrator, administrator, business executive or manager, public relations, and marketing.

Conventional
• LIKES: You like to keep things in order and prefer the highly ordered activities that characterize office work. Likes to work with numbers, records, or machines in a set, orderly wayYou like clear rules and instructions.  You are good with details and very careful to do things the right way.
• They fit well into large organizations but do not seek leadership
• They respond to power and are comfortable working in a well established chain of command
• Such people describe themselves as conventional, stable, well-controlled, and dependable
• DISLIKES: They dislike ambiguous situations, preferring to know precisely what is expected of them and They have little interest in problems requiring physical skills or intense relationships with others, and are most effective at well-defined tasks
• SIMILAR TYPES: The two work environments that are closest to the Conventional type are Realistic and Enterprising. The farthest away is the Artistic type.
• PERSONALITY TRAITS: Conforming, obedient, persistent, practical, self-controlled, conscientious, and valuing orderliness and routine.
• CONVENTIONAL OCCUPATIONS: file clerk, data entry, personnel clerk, secretary, cashier, reservations agent, accountant, computer programmer, analyst, operations, database management, and web page design.


Data, People, Things, and Ideas
A second way of looking at occupations is to measure them in terms of Data, People, Things, and Ideas.
• Realistic people like working with Things in occupations such as chef, air traffic controllers, carpenters, and builders.
• Investigative people like working with Data in occupations such as medical technician, computer programmer, engineering, and Science.
• Artistic people like working with Ideas in occupations such as commercial artist, musician, and interior design.
• Social people like working with People in occupations such as teaching, counseling, and care of elderly people.
• Enterprising people like working with People and Data in occupations such as business leadership, marketing, entrepreneurship, and politics.
• Conventional people like working with Data in such occupations as accounting, administrative assistance, and paralegal.