Climate change is causing an increasing number of extreme climate events, such as floods, landslides and heat waves. Although all will be affected, exposure, sensitivity and adaptive capacity vary among different population segments and the effects will be disproportionally distributed in a society.   The aim of this study is to gain a deeper understanding of how factors related to the exposure, sensitivity and adaptive capacity shape the vulnerability of different populations segments. It qualitatively explores how key stakeholders in municipalities perceive and construct social vulnerability in relation to climate change with a specific focus on thermal comfort (i.e. heat waves). Earlier literature on natural hazard vulnerability and social vulnerability has identified a number of factors that explains variance between different populations segments and differences in morbidity. We seek to understand how the planning and operational staff in municipalities, and the vulnerable themselves, understand social vulnerability and which adaptation responses at different levels they identify. Thus, the top-down approach from earlier literature is triangulated with a bottom-up approach.