Considering that the OSM data model doesn’t know anything about polygons and multipolygons, it is amazing that there are more than 200 million (multi)polygons in OSM. Let’s have a look at those polygons and multipolygons, at closed ways and relations, at the different ways of tagging areas, and at the myriad ways of getting those things wrong. And then lets talk about how we are going to fix things. This workshop is not about a new area datatype, it is about making the best out of the existing datatypes. It is part of an ongoing effort to ease mappers’ lives and the life of OSM data users by simplifying tagging rules and fixing invalid data.