Most visitors find that once they arrive in Aspen or Snowmass, they have little need for a car:  

Extensive and frequent bus service is free in Aspen and Snowmass.

Free skier shuttle service to all four ski mountains.

Many destinations - hotels, shops and restaurants - are within comfortable walking distance.

Taxis and limos provide service to and from the airport and virtually any other destination in the Aspen/Snowmass area.

Many of the larger lodges provide courtesy van service to or from the airport and around town.