This thesis discusses the importance of implementing an ERP system in a company, which radically redesigns business processes and the internal organization of the company, which at the same time marks a break with the previous way of doing business. In situations of declining company performance and with the aim of gaining a competitive advantage, such changes in organizations are necessary. In order to maintain the competitiveness of the company in the long term, it is necessary to continuously analyze, harmonize and improve business processes with the aim of timely change. Since every organization functions in a multitude of interwoven business processes, ERP as an integrated information system enables simpler monitoring and interconnection of individual parts of the information system in such a way that the data of certain business phenomena is stored in one system, and at the same time it is possible to use them in several subsystems. The chapters of this paper will analyze the activities that preceded the implementation of the SAP S/4 HANA integrated ERP system in the company Hrvatske šume d.o.o. as well as key changes in the company's processes after implementation, which implies the standardization of processes in finance and accounting, payroll, planning and controlling, real estate management, forest management, etc. In this way, users are enabled to use a unique database, enter data only once and on the place where they are created with the possibility of visibility to everyone based on the assigned powers, in real time. The introduction of such an integrated information system is very demanding, however, its implementation enables the standardization of business processes within the organization and the management of the company's operations according to internationally adopted standards.