The process of data harmonization starts with a description of data sources and mapping of differences among heterogeneous source and target data sets. The semantic differences usually include incompatible data schemas (structures, different data types, domains etc.) and differences in content (different values for the same entity). While the second type of differences is difficult to be solved in an automated way, the first type can be described by the new tool HALE, developed within the HUMBOLDT project. The HUMBOLDT Alignment Editor (HALE) allows to interactively specify transformations between models at a conceptual schema level. It is possible to rename attributes, to make reclassification (classification mapping), to change geometric types, to change values using various mathematical expressions, to set default values etc. The paper presents features, functions and results of testing harmonisation process for selected geodata. The process of data integration into common schemas which are INSPIRE compliant is discussed. The INSPIRE theme Hydrography is used as a core of the solution. Finally the schema transformation performed with HALE is executed with the help of other HUMBOLDT tools (i.e. conceptual Schema Transformer) to perform required data transformation.