Exclusive Contract
Exclusive contracts are either contracts between the model and the model agency, or the model and the customer.
The customer is signing a contract with the model to make sure that she only works for this customer and not for any competitor of the customer. This contract is normally just for a limited period of time. Normally the model gets a higher model fee, because she is not allowed to work for competitors.
The contract between the model and the model agency includes important details of the booking. This exclusive contract stated that the model is only allowed to work for one model agency. That is only allowed if the agency pays the model an extra monthly fee until the contract ends.