This review summarizes the current state of science in measuring the built environment for physical activity. It discusses three main types of measures: perceived (self-reported), observational (audits), and GIS-derived. Perceived measures are obtained through surveys and questionnaires, while observational measures involve systematic observations of the environment. GIS-derived measures use existing data and spatial analysis to assess environmental characteristics. Perceived measures include questionnaires that assess access to recreational facilities, land use, traffic, aesthetics, and safety. These questionnaires vary in length and are often used in mid-sized to large cities. Observational measures involve audits to systematically observe features of the environment, such as street patterns, sidewalks, and public spaces. GIS-derived measures use spatial data to analyze environmental variables like population density, land-use mix, and access to recreational facilities. The review highlights the variability in operationalizing common GIS measures, such as population density, land-use mix, and access to recreational facilities. It also notes the need for further development of measures to improve their technical quality, understand their relevance to different population groups, and assess their utility for science and public health. The review emphasizes the importance of reliability and validity in all types of measures, with a focus on content validity, construct validity, and criterion-related validity. The review also discusses the challenges and trade-offs associated with using each type of measure. Perceived measures can be affected by response rates and the accuracy of self-reported data. Observational measures are time-consuming and require trained personnel. GIS-derived measures require access to spatial data and can be affected by data quality and temporal changes. The review concludes that while there has been significant progress in measuring the built environment for physical activity, further research is needed to improve the accuracy and relevance of these measures. This includes developing more reliable and valid measures, understanding their applicability to different populations and settings, and ensuring that they are useful for both scientific research and public health initiatives.This review summarizes the current state of science in measuring the built environment for physical activity. It discusses three main types of measures: perceived (self-reported), observational (audits), and GIS-derived. Perceived measures are obtained through surveys and questionnaires, while observational measures involve systematic observations of the environment. GIS-derived measures use existing data and spatial analysis to assess environmental characteristics. Perceived measures include questionnaires that assess access to recreational facilities, land use, traffic, aesthetics, and safety. These questionnaires vary in length and are often used in mid-sized to large cities. Observational measures involve audits to systematically observe features of the environment, such as street patterns, sidewalks, and public spaces. GIS-derived measures use spatial data to analyze environmental variables like population density, land-use mix, and access to recreational facilities. The review highlights the variability in operationalizing common GIS measures, such as population density, land-use mix, and access to recreational facilities. It also notes the need for further development of measures to improve their technical quality, understand their relevance to different population groups, and assess their utility for science and public health. The review emphasizes the importance of reliability and validity in all types of measures, with a focus on content validity, construct validity, and criterion-related validity. The review also discusses the challenges and trade-offs associated with using each type of measure. Perceived measures can be affected by response rates and the accuracy of self-reported data. Observational measures are time-consuming and require trained personnel. GIS-derived measures require access to spatial data and can be affected by data quality and temporal changes. The review concludes that while there has been significant progress in measuring the built environment for physical activity, further research is needed to improve the accuracy and relevance of these measures. This includes developing more reliable and valid measures, understanding their applicability to different populations and settings, and ensuring that they are useful for both scientific research and public health initiatives.