Since 1997, successive Labour Governments have prioritised action on climate change. The United Kingdom is commonly perceived to be an international leader in terms of its global diplomatic efforts and, to a lesser extent, its domestic policy response. However, the UK's carbon dioxide emissions from the transport and housing sectors are increasing. In this paper, we focus on the transport sector and examine the extent to which policies have encouraged decarbonisation, and the underlying reasons behind their relative success or failure. Despite initial good intentions, policies aimed at improved efficiency, encouragement of less polluting modes of transport and reductions in demand have fallen short. Underlying this failure, we argue that the transport sector's traditional prioritising of the immediate economic implications of policy and the government's fear of being seen to impinge upon personal mobility have resulted in too strong a reliance on technological solutions rather than measures that seek to curb demand through behavioural change. We conclude by arguing that unless demand for carbon intensive forms of transport is reduced, the government will struggle to meet its increasingly ambitious carbon dioxide reduction targets, but that important new legislative initiatives at national and EU level offer chances for a more concerted approach.