An arrangement with one brand for the duration of a fashion week: the model walks for them only and turns down every other show.
What each side gets
The designer gets a face the audience has not already seen in other collections — the show reads as a whole rather than as an assembly of the same people who walked next door. The model gets a visible start, a fee above the usual rate, and the press attention normally reserved for whoever opens a show.
What it costs
Every other show of the season. If the house that takes you exclusive turns out not to be a major one, you have traded a week for a single exit — and that is the main risk in the decision. Which is why it is taken together with the agency, weighing who else has called and what you are giving up.
Kinds
Full — no other shows at all. Partial — limited by city, by days, or by a set of competitors: no other houses in the same group, for instance, but everyone else is fine.
What has to be written down
Term and territory. Compensation — an exclusive is paid separately from the exit itself. And what happens if the show is cancelled: a season given up has to carry a payment, otherwise the entire risk is yours.
An exclusive is one of the rare moments when a beginning model has something to negotiate with, and it is worth using.
How it plays out in practice
The offer comes through the agency in the middle of castings, and the answer is wanted the same day: the designer has a line-up to close. Which is exactly why the terms are discussed before the season, so that the moment is for deciding, not for finding out.