For the measurement and international comparison of effective tax burdens, the ZEW has already achieved a great knowledge. The ZEW has developed own approaches (e.g. European Tax Analyzer) and applies other models (e.g. Devereux/Griffith) for the measurement of international effective tax burdens. This includes the development of software solutions.Also the ZEW has a huge amount of data about the taxation systems in many different countries including the member states of the European Union and some important states outside the EU. These data about the different types of taxes, the tax bases and the schedules hasnt been collected and stored at a central point or location yet.Against this background the aim of the project is twofold. First of all, the whole knowledge about taxation systems at the ZEW shall be collected and stored in a computer based Database (Taxation Knowledge Database) to create an archive and to make it easier to get information about a special state of interest. The second aim is that all software solutions of the ZEW as well as external ones should be able to access this database. This should lead to a much more efficient way to receive information and to increase their quality.