1. The Consultant : A consultant is an experts person who possesses a high level of expertise in the area. He guide and educate the executives regarding establishing the experts systems.
2. The Experts Interface or Intelligent Front End: This consultant is an expert on using some complex computer system or operation and assists an inexperience user to use the established experts system.
3. Assistant : These people have a lower level of expertise than those persons which undertake routine job and leaves the executives to make final difficult decisions. This is the easiest and cheapest class of experts system to build and has important in business.
4. The Idiot Servant: These workers have a small amount of intelligence and low level of expertise and a great deal of information. The work of this class is to use its limited expertise to decide what information is should retrieve and offer to its user. The most common example of this class is maintenance experts which retrieves detailed information on part of a machine as and when they are required.