An agent company is ANYONE who might sell the product, for example:
Each agent must have a primary contact - even if it is just a generic one (eg reservations). This is used if confirmation emails are sent to them for reservations.
Multiple contacts can be defined for different roles (eg Marketing or Reservations)
Contacts have log ons and passwords associated with them - this allows them to log on, check availability and make bookings direct via the Internet should they wish.