OpenStreetMap (OSM) is a collaborative project to create a free, editable map of the entire world, built primarily by volunteers using GPS devices, aerial imagery, and local knowledge. Founded in 2004, it has grown into one of the largest and most successful crowdsourcing initiatives in history, with millions of contributors mapping roads, buildings, land use, and points of interest across every country. The project operates under open-data principles, making its geographic database freely available for any use. OSM data underpins applications ranging from humanitarian disaster response to commercial navigation and urban planning analysis. It is particularly relevant in Citizen Science, Urban Planning and Software Engineering.

OpenStreetMap supports crowdsourcing, community-based and open source collaboration and is suited for community-scale initiatives in remote and hybrid settings.

OpenStreetMap is classified as a well-documented case study, indicating broad adoption and available documentation. This case study examines the collaborative practices at OpenStreetMap Foundation, drawing on experiences since 2004.