Valet parking is a parking service offered by some restaurants, stores, and other businesses. In contrast to "self-parking", where customers find a parking space on their own, customers' vehicles are parked for them by a person called a valet. This service either requires a fee to be paid by the customer or is offered free of charge by the establishment. Explanation A valet is usually an employee of the establishment or an employee of a third-party valet service. When there is a fee, it is usually either a flat amount or a fee based on how long the car is parked. It is customary in the United States to tip the valet who actually parks the car. Valet parking is most often offered (and is most useful) in urban areas, where parking is scarce, though some upscale businesses offer valet parking as an optional service, even though self-parking may be readily available. For example, in wealthy suburban areas like California's Silicon Valley, some hospitals (like Stanford University Medical Center) offer valet parking for the convenience of patients and their visitors. Some cars come with an additional key, known as a valet key, that starts the ignition and opens the driver's side door, but prevents the valet from gaining access to valuables that are located in the trunk or the glove box. Efficiency The main advantage of valet parking is convenience. Customers do not have to walk from a distant parking spot carrying heavy loads. Many disabled drivers rely on valet parking when they can't walk from and to a distant parking spot. Likewise, people who do not have time to search for a parking spot can valet park without the hassle. Valet parking is especially convenient in bad weather. Most professional valet attendants are well insured, and knowledgeable about nearly every make and model of car and their quirks; including aftermarket alarm systems, and keyless ignitions. An advantage of valet parking is that it is possible to pack more cars into a given physical space, in what is generally known as "stack parking". The valet holds all the keys and can park the cars two or more deep, as they can move cars out of the way to free a blocked-in car. Another type of stacking is called lane stacking. This method is useful for events where guests all arrive around the same time, such as for a wedding reception.