In the last century, heatwaves in Sweden occurred once every 20 years (the last being in 1975). Since the start of the new millennium, four heatwaves (2003, 2007, 2010 and 2018) have been already experienced. The frequency of these events is expected to further increase due to climate change; they will occur once every three to five years towards the end of the century. Heatwaves are already leading to increased mortality. Botkyrka is a municipality in Stockholm County in east central Sweden, not far from the capital with a population of 91.925 inhabitants. In 2010, the municipality experienced prolonged high temperatures, which led among other things to problems in elderly, retirement and nursing homes. The residents were severely hit by the heat and the staff had problems to look after them well enough. Extensive efforts, partly in the frame of a project held within the Climatools program, have been made in the municipality of Botkyrka to reduce the health risk of heatwaves. Staff of elderly, retirement and nursing homes has acquired knowledge on heatwaves risk and on checklists that must be followed in case of heatwave warnings. If necessary, additional staff can be called and activated to ensure further support to safe care. Therefore, during the 2018 heatwave, the municipality was far better prepared and equipped than in previous situations. Botkyrka is also supporting actions aiming to improve indoor thermal comfort and to create “cool-spots” in various areas of the city.