Doctoral dissertation information transparency on web pages of educational institutions in the Republic of Croatia gives an insight into the fulfillment of the obligations of this public authority, i.e., the proactive publication of information of secondary schools according to Article 10 of the Law on the Right of Access to Information (Official Gazette 25/13, 85/15, 69/22). The dissertation aims to determine the qualification and execution of obligations of the information officer as a special official who is responsible for the resolution and realization of the right of access to information and proactive publication of information by public authorities, as well as the importance and influence of the Information Commissioner as an independent body that supervises the implementation of the Law on the Right of Access to Information and annually submits a report to the Croatian Parliament. Transparency and openness of public authorities are fundamental values of a democratic society and good governance, and the right of access to information gives citizens and legal entities a wide opportunity to seek and obtain information of public nature, thus pushing the boundaries of transparency and openness. The right of access to information, guaranteed by the Constitution of the Republic of Croatia and the modalities of its realization are regulated by the Law on the Right of Access to Information, which prescribes a series of obligations for public authorities regarding the provision of information at the request of the user, proactive publication of information; at the same time, it establishes supervision and monitoring mechanisms in the person of the Information Commissioner as an independent institution that protects, monitors and promotes the right of access and reuse information. The Commissioner submits to the Croatian Parliament an annual report on the implementation of the Act. Public authorities are obliged to publish information relevant to their work and organization on their official websites in an easily searchable manner, preferably in accordance with the 'three mouse clicks' rule. Analytical monitoring of the websites of secondary schools in the Republic of Croatia determined the level of proactive publication of laws, regulations, general acts, and other documents related to their field of work. In addition to the analysis of websites, a survey of 41 information officers and an in-depth interview with the Information Commissioner were conducted. The results of the research indicate that the websites of secondary schools do not contain all the information that they are obliged to publish according to the Act on the Right of Access to Information as a public authority and that schools have insufficiently trained information officers. The development of the degree of transparency and proactive publication of information by secondary school 13 institutions, and the uneven approach to the publication of information by the examined institutions clearly shows that progress can be made in the area of transparency.