Exposure to hot weather can lead to heat-related illnesses (e.g., heat exhaustion) and/or trigger the exacerbation of pre-existing chronic diseases (e.g., cardiopulmonary diseases). 1 This is particularly concerning because hot weather is becoming more frequent, more intense, and longer-lasting. 2 To protect public health from the adverse impacts of hot weather, it is imperative to develop effective, accessible, and sustainable heat adaptation strategies. To inform the development of these strategies, the epidemiology research community needs to conduct high-quality heat health impact assessments to generate actionable evidence by leveraging the best available climate and health data, adopting recommended epidemiological designs, and judiciously interpreting research findings. The German study by Zhang et al., published in this issue of The Lancet Regional Health—Europe, 3 is a salient example of such research endeavours.