General agencies often accept several clients from the same local market. That may suit the agency, but it creates an obvious conflict when each client is paying for local search, reputation and competitive advice.
Define the territory clearly
Protection should not be a vague promise. The written proposal should describe the town, city, county, radius or branch locations covered, along with any exceptions.
Protection creates accountability
When the partner cannot simply sign the closest competitor, it has a stronger reason to invest in the long-term success of the relationship.
It also requires sensible limits
A very large protected territory may need a different price and capacity commitment. Exclusivity must be commercially workable and transparent for both sides.