To be comprehensive, gender-disaggregated data should be collected about many dimensions of inequality beyond gender, including ethnicity, caste, location, age, poverty, employment status and ability. Such collection requires diverse methods, including censuses, surveys, interviews, community-based monitoring systems, time-use surveys and measures of unpaid work. The regular collection of the gender-disaggregated data necessitates reliable data systems, creating and maintaining effective data collection and management systems, however, remains a challenge for many governments, w'hich still need to improve and expand their data systems.