Increasing demand for animal products has contributed to the increase in biogeochemical fluxes, leading particularly to gaseous ammonia, methane and nitrous oxide emissions into the atmosphere. Air pollution from livestock production systems has thus become a major environmental issue at local (ecosystem eutrophication and acidification), regional (air quality) and global (climate change) scales. Developing accurate knowledge on the sources and magnitude of gas emissions from the livestock sector is essential to reduce emissions, while meeting other societal expectations, and to implement effective regulations. To this end, the ELFE database was recently developed. It currently contains ca. 5 200 gas emission measurements extracted from 345 publications of the international literature published from 1964 to 2018 by first authors from 37 countries. One of its innovative aspects is the structured and comprehensive description of both the livestock system and the measurement method associated with emission data. Among the gases emitted by livestock systems, ammonia represented 40-80% of emission values and slurry 45-81% of production systems, depending on the animal produced. This database will contribute to improved emission factors for national inventories by more thoroughly considering factors influencing emission levels and data quality. It highlights the need for shared and standardized reporting protocols of both the livestock system itself and the measurement conditions, to allow for thorough comparisons and to reduce uncertainty in unit conversions.