An important way to reduce the greenhouse gas emissions that transport produces is to encourage and enable people to travel less. People travel less overall when they switch from private vehicles to public transport, walking or cycling, for reasons that will be explained. They travel less if their work is closer; if shops, health services and education are closer; and if family, friends and leisure activities are as well. They travel less if several purposes of travel can be covered in one trip, which is more likely if the places they need to visit are closer.

Public transport (mass transit) is critical to the proper functioning of any city, town or rural area. A range of transit modes offer different capacity opportunities, and therefore the potential for high or low impact on car use. Higher capacity systems cost more to put in, but offer much more potential reduction in total transport costs and greenhouse gas emissions. The social, economic and environmental costs of not having an efficient mass transit system never go away, so it is really a case of stemming these costs earlier or later.

Cycling is a cheap, healthy, efficient form of transport that only produces greenhouse gases in the production and distribution of bicycles, and it is very well suited to short to medium travel distances. It is also very inexpensive for cities and other localities to develop cycling routes, relative to the cost of other transport infrastructure.