Topic of the master’s degree thesis is: Changes in the process of building and at roles in the implementation of BIM at the case of public building. Selected public building for the example is the building Faculty of Civil Engineering Osijek. In the theoretical part of the work it is explained concept of the BIM and its advantages in the engineering profession. In the review of the legal framework of the European Union from the January 2014, there are singled out directives concerning the application of BIM software in contracts on public projects and design competitions, and advantages in adopting such a tool for public procurement projects. It is explained the concept of public building according to law and regulations. Greater attention has been given to the description of changes in the construction project, to the dynamics of changes in the activity plan of the project in the implementation phase. Management of project changes were processed through the chapters about the types of project changes, basics of project changes, causes of unplanned changes at the scope of the project, as well as techniques to minimize changes to the project. In the practical part of the work it is identified the impact of the changes realized on the facades of building Faculty of Civil Engineering Osijek by the analysis of key documents which had effect at the project changes. They are digitally modeled concrete carriers of the building, carrier "A" and carrier "U" by the competition entry, preliminary design and the main project. In total has made 6 models, for each carrier 3 solutions. Modeling was performed in software for BIM design and documentation ArchiCAD from the company Graphisoft, a comparison is made between carriers by the geometric characteristics of the carriers obtained from the model. Results are interpreted with table for each model and with the diagrams of comparison. A survey was taken with questionable online form between the participants in the project and interviews with some of participants. The survey includes three parts: the first; general questions about the role of participants in the project, second; questions related about of the role of participants in the changes identified at the facades of the building and, a third; estimates of assumptions at the splitting roles and using of documentation in various stages of the project including participants own comments on the possibilities of improving at the this topic. The analysis of responses identified the participants in the various stages of the project, roles and responsibilities, the documentation that was used for communication. There are founded ways of possible improvements by applying BIM approach in the methods and media communication in the project, there are analyzed additional skills, knowledge and competencies of BIM project participants and their advantages over the current practice.