The provisions of general tax law contained in the tax ordinance should be stable. In recent years, however, we have seen an intensifying process involving amending this act. An analysis of the changes made proves that they are introduced in connection with the need to counteract tax fraud, the lack of institutions characteristic of modern acts of this type, and the development of new technologies. The continuous modernisation of the provisions of the over-20-years-old ordinance no longer brings the expected results, and in some cases actually leads to the undermining of the fundamental institutions of tax law. There is a need for a new act. Only the adoption of such an act can contribute to the improvement of the stability of general tax law.