The article by Rafael Pérez-Escamilla provides a comprehensive overview of food security (FS) and nutrition security, emphasizing their importance as social determinants of health. The objectives are to clarify definitions, explain the links between FS and nutrition security, summarize measurement approaches, and illustrate applications in monitoring, policy, and research. FS is defined as the condition where people have access to sufficient, safe, and nutritious food, and it encompasses multiple dimensions such as quantity, dietary quality, food safety, suitability, psycho-emotional aspects, and social acceptability. Nutrition security is influenced by FS and other socio-economic factors. Experience-based scales, particularly the US Household Food Security Survey Module (USHSSM), have been instrumental in assessing FS and have been disseminated globally, leading to the development of scales like the Brazilian Food Insecurity Scale (EBIA) and the Latin American Food Security Scale (ELCSA). These scales help in understanding the severity of food insecurity and its impact on health and well-being. The article also highlights the importance of water insecurity scales, such as the Household Water Insecurity Experiences (HWISE) scale, which are increasingly being used alongside FS scales to track water security. Cross-border collaborations have been crucial in advancing FS and nutrition security policies, and the article emphasizes the need for systematic sharing of best practices through networks of researchers and practitioners.The article by Rafael Pérez-Escamilla provides a comprehensive overview of food security (FS) and nutrition security, emphasizing their importance as social determinants of health. The objectives are to clarify definitions, explain the links between FS and nutrition security, summarize measurement approaches, and illustrate applications in monitoring, policy, and research. FS is defined as the condition where people have access to sufficient, safe, and nutritious food, and it encompasses multiple dimensions such as quantity, dietary quality, food safety, suitability, psycho-emotional aspects, and social acceptability. Nutrition security is influenced by FS and other socio-economic factors. Experience-based scales, particularly the US Household Food Security Survey Module (USHSSM), have been instrumental in assessing FS and have been disseminated globally, leading to the development of scales like the Brazilian Food Insecurity Scale (EBIA) and the Latin American Food Security Scale (ELCSA). These scales help in understanding the severity of food insecurity and its impact on health and well-being. The article also highlights the importance of water insecurity scales, such as the Household Water Insecurity Experiences (HWISE) scale, which are increasingly being used alongside FS scales to track water security. Cross-border collaborations have been crucial in advancing FS and nutrition security policies, and the article emphasizes the need for systematic sharing of best practices through networks of researchers and practitioners.