FOSS4G is the acronym for Free and Open Source Software for Geospatial. It is the annual recurring global event hosted by OSGeo, the non-profit organisation that supports and promotes the collaborative development of free and open source geographic technologies and open geospatial data.

This event is for all kinds of people interested in sharing experiences about maps, from developers who write code to users of geomatics software, people who make decisions, researchers, students and anyone who wants to learn, share and meet like GIS interested people.

It attracts over 1,000 practitioners and advocates for free and open source software for geospatial.