Volunteered geographic information (VGI) plays an increasing role in current geodata provision. At the same time, due to its lack of structure, it is hard to use as meaningful input in software applications. In this chapter, we embark upon the unstructured character of VGI and on ways to enrich the structure in order to make it suitable for information retrieval. We describe the characteristics of semantic enrichment and explain how folksonomies and ontologies play a role. We believe that they represent different levels of formality in a semantic reference space and determine the richness of the informationretrieval.