There are a number of steps on the way to achieving a reduction in car use. It should also be noted that having made a change, habitual drivers can relapse into old travel patterns. Relapse may occur if individuals do not feel supported, they feel they are making changes in isolation, the alternatives they are using do not adequately meet their needs or involve too much effort, or they perceive that the need to use cars less has receded. Such relapses may not be permanent. Individuals can cycle through the stages of change several times. Often the change will be longer lasting each time until it becomes habitual.

Individualised marketing campaigns are usually introduced to reduce car use, although they can be used in conjunction with other measures to support those policy instruments and achieve a greater overall impact. Demand impacts may be small initially (although this depends on other policy instruments), but are incremental over time as more campaigns are implemented. Contributions to achieving policy objectives are therefore mainly positive.