The evidence that social norms – informal rules of acceptable action within a given group – influence people’s health-related choices is abundant and cross-sectorial, ranging from health-related behaviours such use of contraception, handwashing, alcohol use and/or smoking, to social practices and behaviors such as corporal punishment, child marriage, sexual harassment and sexual assault. Following the large body of literature, especially coming in health promotion, underscoring the importance of addressing harm - ful social norms to improve people’s health, social norms theory has long been used to inform public health policy and practice. Even though several different theoretical perspectives exist on what social norms are and how they affect people’s practices, much contemporary research and practice in public and global health has adopted theory and terminology by Cialdini and colleagues, whose Focus Theory of Normative Conduct defined social norms as (1) one’s beliefs about what others in one’s group do (descriptive norms), and (2) the extent to which one believes others as approving or disapproving of something (injunctive norms).