The document discusses car sharing as an alternative to private car ownership. It notes that car sharing can provide more efficient mobility through shared use of vehicles. Each car sharing vehicle replaces 4-8 private cars, freeing up parking spaces and reducing urban space needed for cars. Studies show car sharing leads to reductions in car mileage, CO2 emissions, and energy use as members use public transit and bikes more when not using a shared car. The document advocates expanding car sharing in European cities to improve sustainable transportation.