Introduction: Given the growing health impacts on the population resulting from climate change, there is a real need to determine whether the heat adaptation measures promoted by public health authorities are being adopted by the relevant populations and organizations. Materials and Methods: This article reviews the approaches adopted by the Institut national de santé publique du Québec (INSPQ), through the Observatoire québécois de l'adaptation aux changements climatiques (OQACC), and by Santé publique France to characterize heat adaptation behaviors and perceptions of risk associated with this hazard. Using differential item functioning analysis, certain items from the questionnaires used in both countries are then compared. Results: Regarding the variables investigated, both approaches focus on: 1) attitudes toward a climate change adaptation behavior or intervention; 2) perceived or anticipated pressures to act; 3) perceptions regarding the challenges of adopting appropriate behaviors; 4) perceived vulnerability; 5) the perceived severity of risks and the estimated effectiveness of an adaptation behavior or intervention. While the Santé publique France approach is intended to be descriptive, the objective of the Quebec approach is to develop indices dedicated to the longitudinal monitoring of adaptation and to identify the psychosocial determinants of the adoption of these adaptation behaviors. A France-Quebec comparison was also conducted through an analysis of the differential functioning of items on the questions measuring, in both population-based studies, similar heat adaptation behaviors. Discussion-conclusion: analyses of item differential functioning demonstrated that questions formulated in a very similar manner could lead to divergent results depending on the cultural context, hence the need for caution before adopting adaptation behaviors used in another cultural context. Both the work of Santé publique France and that of the OQACC help to make the concept of adaptation to climate change more concrete and contribute to improving its measurement at different population and spatial scales.