According to Wikipedia (“Consultant,” Wikipedia, retrieved April 5, 2021) “a consultant is usually an expert or an experienced professional in a specific field and has a wide knowledge of the subject matter. The role of consultant outside the medical sphere (where the term is used specifically for a grade of doctor) can fall under one of two general categories.” One is the “internal consultant,” who works in an organization and whose specialization is valued by certain internal clients, namely, other departments or individuals. The other category—the “external consultant”—who is hired on a temporary basis by a consulting firm or other agency and is paid a fee for the expertise provided. Wikipedia states that:

The external consultant is the subject of this chapter. There are 45 types of this worker listed on the Wikipedia website, of which we will look at a representative sample of 11. In general, consultants meet, in nearly ideal fashion, the six criteria for occupational devotion. They are deeply knowledgeable and experienced in their specialty, and each opportunity to apply this background is unique. Consultants are hired to solve problems, which opens the door to creative or innovative solutions on their part. Further, they are often self-employed, acquiring thereby reasonable control over the amount and disposition of time they put into it each day. It goes without saying that, since these workers have aspired to be consultants, they have both a taste and an aptitude for the core activities. The social and physical milieu in which they must work may not always, however, be ideal. This can be a problem when they work onsite with a client, as opposed to working in their professional office .