The harmonization of spatial data sets is one of the major challenges for the development of spatial data infrastructures (SDI). Therefore, schema transformations are applied to convert the original data into a unified data schema using specified transformation rules, called the schema mapping. For the implementation of INSPIRE (Infrastructure for Spatial Information in Europe) a
generic description of the schema mapping in the Rule Interchange Format (RIF) is proposed to achieve interoperability of different schema mapping systems. RIF was primarily designed for the exchange of rules between different rule systems. This article shows how to deploy RIF for the schema mapping of spatial data and that RIF meets all the requirements of INSPIRE on the functionality of such a mapping language. The example of the HUMBOLDT Alignment Editor (HALE) demonstrates the integration of RIF in existing schema mapping software.