A table reservation is an arrangement made in advance to have a table available at a restaurant. While most restaurants in the vast majority of the world do not require a reservation, and some do not have a policy or simply any channel for making one, so-called higher-end restaurants mainly in overcrowded cities often require a reservation, and some may have tables booked for weeks in advance. At particularly exclusive venues, it may be impossible to make a reservation on the same day as the planned visit.