CJ case law reveals that European law is having an increasing influence on procedural tax law. In this article, an overview of the influence of European law on procedural tax law will be depicted. Procedural tax law is here defined as the totality of rules regarding the manner in which material tax liabilities should be expressed in the actual payment of tax. The authors will describe the above-mentioned influence in two articles. In part 1, the authors first outline the European law framework against which domestic procedural tax law should be tested. Subsequently, they discuss in more detail the notable influence of European Community (EC) law to several specific domestic rules and concepts of procedural tax law, such as entitlement to compensation for EC infringements, unlawful administration of justice, rules of evidence, and fixed payment of procedural costs. In part 2, the authors discuss whether national time limits, the impossibilities for an administrative body to re-examine an earlier decision, procedural legal effect, and the principle of res judicata, are compatible with European law.