Guests of Honor
Guests of Honor, or GoHs, are the special guests of your convention.
Different conventions have different numbers of GoHs. Some select guests based on thematic "guest slots', such as Author or Pro Guest, Scientist, Artist, Fan, Toastmaster, Editor, Filker, Media Guest, etc.
Different conventions provide different benefits to Guests of Honor for their convention. Most volunteer-run conventions that are not run for profit do not pay appearance fees. However, it is fairly standard to cover travel expenses, provide a hotel room, and provide for the Guest's food while they are at the convention, either through a per diem or by offering to cover all their expenses. As I heard one author put it, the convention should try to make sure it doesn't cost the guest anything to attend the convention. Depending on their budget, conventions may also offer to cover expenses for a companion of the Guest of Honor, to travel to the convention with them. This is considered a Good Idea, if you can afford it. Some conventions also have a policy whereby GoHs receive lifetime memberships to the convention, to encourage them to return in future years.
There are both general and specific expectations of what a convention will get in return from their GoHs. These may include that the GoH should participate in some minimum amount of programming, that they should say something for a GoH Speech perhaps, and that they will allow the convention to use their name to promote the convention.
All benefits offered and expectations held in return should be expressed to a prospective GoH when they are invited to be a Guest of Honor. This is commonly done in an invitation letter, which should also include a description of the event, how wonderful it is, and why your group would particularly like that person to be a guest.
Every Guest of Honor should be assigned a Guest Liaison, to be their point of contact throughout the year and their personal shepherd during the convention itself.