Gender-disaggregated data is often confused with data disaggregated by sex. But biological sex disregards the socially built power relations and gender norms that exist between and among males, females, and people with other gender identities, ignoring the cultural and systematic disparities that exist. Gendered power relations have significant influence on data collection efforts, health-seeking behaviors, vulnerability to risk factors for non-communicable and other diseases, and the impact of health policies. To understand the root causes of gender inequalities, gender-disaggregated data asks the “who questions:” Who does which tasks? Or who has a higher prevalence of a particular disease? Gender-disaggregated data is important to better identify exposure routes.