The ArcGIS Editor for OpenStreetMap is designed to help ArcGIS Desktop 10 users to become an active member in the growing community of users building an open and freely available database of geographic data.
The provided tools allow you to download data from the OSM servers and store it locally in a geodatabase. You can then use the familiar editing environment of ArcGIS Desktop to create, modify, or delete data. Once you are done editing, you can post back the edit changes to OSM to make them available to all OSM users.
This site provides access to the released versions of the ArcGIS Editor for OpenStreetMap (OSMEditor), the source code, as well as documentation and issue tracker.