Consultancy?

What really is the definition of "consultant" and "consultancy"? Has it been so spoiled and rotten that it has deterred from the focus on expertise to no-practical-knowledge? Donors have brought in so many "consutant" positions, for foreigners and Cambodians alike. They pay a hell lot of money, but the kinds of people, most, if not all, they recruit are strongly questioned. See, some foreigners come with lower degree than Cambodian counterparts and have no relevant knowledge of Cambodia whatsoever, earn a thousand times than a normal Cambodian, but their work outputs are received from the sweats of Cambodian subordinates. Have they any ethics? Aside from that, they hire "national consultants" who, in all their lives, have only been in schools. They may have "work experience" (after all, work can be anything right?) but they really have questionable practical knowledge on "Cambodia" and the things associated to their "consultancy work", and so the position of "national consultants"? Gee, what a shame! They earn alot of money but they really shouldn't be proud of it since it is really no different from corruption. I mean, any people with degrees on any subjects can choose these kinds of work in any topics whatsoever as Cambodia is being inundated with "consultancy works" and intellects don't give sh$&%^ about academic morals, being slaves to money. What then is a consultant? Beats me!!! Now would you please help solve the English, if not the math??!?