The recent growth in European use of mobile air-conditioning (MAC) in transport is examined with reference to the experience of the longer-established trend in the buildings sector and to experience in the US. Air-conditioning is identified as significantly undermining improvements in energy efficiency, whilst the penetration of MAC is observed as having been particularly rapid and deep compared with static air-conditioning (SAC). A conceptual framework for the adoption of MAC is then proposed, which draws on sociological and psychological concepts as well as technical considerations in characterizing the processes influencing the adoption and use of MAC. The availability of empirical evidence to validate this model is then considered, with the finding that significant gaps in knowledge exist about why MAC is adopted, who benefits from its adoption, how the systems are used in practice, and the extent of satisfaction of travellers with the comfort of the environments of 'mobile buildings'. Although social norms and behaviour with respect to MAC are flexible, and hence subject to influence by climate change policy, significant further research is required to inform the specification of that policy.