While different forms have emerged around the world, a community car share essentially involves an organized group of participants (usually required to be members) with one or more self-accessing shared vehicles, the usage of which is booked in advance for short periods of time. Typically, users are required to be members.
Car Sharing in Smaller Communities
While car sharing is highly concentrated in major urban areas, numerous examples exist outside of cities. In many ways, the organization and operation is closely linked to differing geographic context and target market.
Smaller and more rural communities tend to have a high degree of personal involvement by members, in some cases by volunteers. Studies have shown that a local champion is more important in making rural car sharing feasible than factors such as extensive public transportation.  Other smaller communities share administration with a parent organization.
Three main types of car sharing organizations (CSOs) dominate the North American market. For-profit CSOs are privately held companies. Non-profit CSOs are incorporated as tax-exempt organizations. Cooperative CSOs are run by members that join by purchasing a “share” in the organization, which essentially acts the same as refundable deposits used by for-profit and non-profit operators. 
Most car share programs are run separately from the government, however many in Europe are run by transit agencies.
Local government agencies are ideal partners in setting up or becoming partners in a community car share program. They have multiple goals beyond reducing GHG emissions, such as reducing congestion and need for parking, that car sharing can help them achieve. Local governments also have a great deal of control over planning, transportation, and parking – each of which can help shape conditions that will lead to the success of car share programs. 
Most CSOs offer services for distinct personal and business users. Personal users join as an individual or a household and use the vehicles for personal use. Business users join to make car sharing vehicles available for employees. For the business, this can take the place of a fleet, taxi use, or personal auto reimbursement; replace employee parking; and provide incentives not to drive to work. Research has shown that the second most popular reason for driving to work is to run errands . Making car share vehicles available for employee use can eliminate the need for that employee to drive to work and increase their overall job satisfaction.
Most CSOs use a combination of the following payment methods:
Per hour reserved.
Per kilometer driven.
Monthly or annual administration charge.
Refundable deposit or credit check. 
Most CSOs provide a core fleet of four-door compact cars. Larger fleets provide specialty vehicles as well, such as pickup trucks or higher-end vehicles. Clean-fuel technology, particularly hybrid technology, has become increasingly popular lately due to increased fuel-economy compared to conventionally fueled vehicles.  Using these vehicles obviously increases the GHG reductions achieved by implementing a community car share program.
Community car share programs lead to:
Reduced vehicle ownership.
Reduced vehicle kilometres travelled.
Reduced parking demand.
Increase in public transportation use.
Increase in individual and household’s ability to access an automobile.
More efficient land use.
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 Adam Millard-Ball, Gail Murray, Jessica ter Schure, Christine Fox, and Jon Burkhardt, (2005). Car-Sharing: Where and How It Succeeds. Transit Cooperative Research Program.