Tax supervision is the process of establishing facts relevant to taxation carried out by authorized officials of the Tax Administration, tax auditors, tax inspectors and other civil servants authorized to conduct it with the taxpayer and other persons. The subject of tax supervision is the verification of one or more types of taxes and / or contributions in one or more tax periods, the verification of relations between company owners and companies in companies, and the verification of facts unrelated to the performance of activities by natural persons. Tax supervision must be efficient and effective, and this is achieved through good preparation and detailed preparation of tax supervision, and careful preparation of the factual basis that is the basis for correctly determining the correctness of calculation and payment of taxes and other public benefits. Tax supervision begins with the delivery of the notice of tax supervision to the taxpayer, and if the official estimates that the delivery of the notice to the taxpayer before the start of tax supervision would jeopardize the purpose of tax supervision, the notice does not have to be delivered. The taxpayer may be represented in the tax supervision by a proxy, tax advisor, legal representative and an expert who assists the taxpayer with advice and serves him as an assistant in the proceedings or ex officio. Authorized officials authorized to conduct tax supervision have been given numerous powers, but also rights and obligations. In the procedure of supervision, authorized persons must adhere to the norms prescribed by the code of ethics, which contains the rules of good behavior of civil servants towards citizens and in mutual relations. The taxpayer has the right to request the disqualification of the official conducting the supervision. If there are legal reasons for exemption, the head of the organizational unit of the Tax Authority that performs tax supervision decides on the exemption of the authorized official who conducts the supervision procedure with the conclusion on exemption. The taxpayer proves the facts established in the tax supervision by giving information, presenting records and keeping and presenting business books, as well as business documentation and other documents. The facts established during the tax audit may ultimately increase or decrease the tax liability, or if no irregularities in the calculation and payment of taxes and / or contributions are identified during the audit process, the liability will remain unchanged. The basis for establishing the facts for taxation are the business books that the taxpayer is obliged to keep on the basis of regulations governing a particular type of tax. For natural persons, the tax base is estimated as the difference between the taxpayer's receipts and expenditures for private needs and / or acquired private property and declared income, ie profit if it cannot be proven that it is taxed. The following acts are adopted in tax supervision; tax supervision notice, conclusion on tax supervision, record on tax supervision and decision on tax supervision. Before drawing up the minutes, the official conducts a concluding interview with the taxpayer. At the final interview, the disputable facts are discussed, the conclusions and its effect on the determination of the tax liability are determined, and legal assessments are made. An appeal may be filed against the decision of the tax supervision, which postpones the execution of the decision until the decision on the appeal is made. Upon termination of tax supervision, an extraordinary legal remedy, a request for reopening of the procedure, may be filed by a decision against which there is no regular legal remedy (appeal). An administrative dispute may be initiated against a decision of the second instance and against a second-instance decision and a conclusion against which an appeal cannot be filed in tax supervision by a lawsuit resolved by the Administrative Court and the Higher Administrative Court of the Republic of Croatia. For tax offenses in tax supervision due to violation of tax regulations, fines prescribed by the laws prescribing certain types of offenses are envisaged.