Paper presented at the 31st Annual Southern African Transport Conference 9-12 July 2012 "Getting Southern Africa to Work", CSIR International Convention Centre, Pretoria, South Africa.
Travel Demand Management (TDM) strategies aim at changing the behaviour of travellers in order to reduce the demand for single occupancy car travel, and to redistribute car users to public and non-motorised modes. The success or failure of TDM strategies – measured by change in vehicle kilometres travelled or modal share – depends upon a robust understanding of what causes travellers to change patterns of behaviour. Many theories have been employed across a range of disciplines to explain behaviour change. A variety of travel behaviour change experiments have been conducted over the previous decade – based either explicitly or implicitly on particular theoretical frameworks – in order to observe the effect of TDM measures and test the veracity of theories. These experiments have typically employed before-and-after survey and control-and-experiment group techniques in measuring behavioural change. This paper reviews, categorises and synthesises theories concerning behaviour change, and the behaviour change experiments that have been conducted. The paper concludes with discussion on the link between theories and experiments, and future research plans.
