The thermal environment in outdoor spaces can significantly influence users’ thermal perception and thus their use of these spaces. The means in which people thermally adapt influence their evaluation of their environments. Consequently, aiming to improve microclimatic conditions in urban spaces can enable people to spend more time outdoors, with the potential to influence the social cohesion of a space and increase economic activity. Since these issues have been rarely approached in the context of the hot arid regions, this study had the purpose of extending the understanding of the complex relation between the outdoor thermal environments, in its micro level, and the use of outdoor spaces in hot arid regions by studying the thermal sensation of the visitors. It aims at finding relationships exist between these issues and cultural and social aspects of their local visitors. Case studies were carefully selected in two different parts of the world (Marrakech in North Africa and Phoenix-Arizona in North America) to represent a variety of users in a similar climatic context. This enabled us to study the effects of the socio-economic and cultural diversity on thermal sensation, behaviour and use of space. Field surveys included structured interviews with a standard questionnaire and observations of the human activities, along with micro-climatic monitoring, were carried out during winter and summer. The analysis consisted of evaluation of the thermal sensation of participants with investigating of the socio-cultural impact on their behaviour in the outdoor space.