In this doctoral dissertation, research on maintenance management in public primary and secondary schools in the Primorje-Gorski Kotar County was conducted to contribute to the theory of maintenance of school buildings, discover problems that affect these buildings and formulate the best practice criteria for their maintenance. Numerous inadequacies in the current management process were identified by methods of surveying school principals and a multiple case study in which the data obtained from school founders were analysed in detail. It is proposed to develop a model that would contribute to more efficient management of schools maintenance, which will achieve proactively and quality maintenance, reduce maintenance resource consumption, minimize downtime and increase customer satisfaction, i.e. staff and students. The maintenance management model in this work is a graphical and descriptive tool that guides school leaders and other stakeholders on how to effectively manage maintenance activities. For the model development, in addition to the data obtained by surveying principals and case studies, data obtained by surveying construction experts and school's users were used, which provides a comprehensive model based on inputs of all important participants in the maintenance of school buildings; construction experts, founders, principals, employees and students. The developed model includes a process diagram, descriptions and guidelines for implementation of individual factors within management functions that include maintenance planning, maintenance organization, maintenance directing, and maintenance control. The model also includes a maintenance prioritization system based on the opinions of experts, staff, and students, developed using the weighted sum method; a mathematical model for predicting maintenance costs based on regression analysis; and a system of performance indicators to assess the performance of the entire maintenance management process. It is expected that the implementation of this model in schools will improve the current processes of maintenance management, especially in terms of a more efficient use of funds for maintenance, where significant shortcomings are currently identified.