Car-sharing is a way for a group of people to share vehicle ownership, thereby reducing costs of ownership. By joining a car-sharing organization, members have access to a fleet of vehicles, parked in a variety of locations. The cars can be reserved for short periods of time, with members paying for their individual usage. Car-sharing is most successful in dense areas, as a supplement to public Transportation.
Proponents advocate that car-sharing has environmental and social benefits. Car-sharing is shown to reduce vehicle trips, as members use cars only when necessary and use alternative Transportation for most other trips. It also reduces the need for households to have extra vehicles, and provides access to cars for people who cannot afford the costs of car ownership. There are two car-sharing organizations operating in Chicago and nearby municipalities, but region-wide coverage is limited.