South Africa requires real estate sales professionals to be licensed by the state in the form of a Fidelity Fund Certificate, so that they can control education and experience requirements and have a central authority to resolve consumer problems.
Principals or Brokers are required to have more education and experience than real estate intern agents or fully-qualified agents.
The person you normally deal with is a real estate agent. The agent is licensed by the state, but must work under the supervision of a principal.
A principal can deal directly with home buyers and sellers, or can have a staff of interns and agents working for him or her.