For decades, the peaks of Sharr Mountains had defined the border between two federal units of Former Yugoslavia, but after the political changes in Central and Eastern European Countries this massif became an intersected mountain. In this thesis work I saw of interest to analyze the status change from a massif unit as part of one state, to a cross-border mountain between two states and its affect on spatial development; - was there any cooperation on mountain management in the past; - how is the current mountain management proceeding on both sides; - which were the opportunities of cross-border cooperation in previous European experiences; - what can be expected from independent mountain side management on report to other side without any environmental assessment; and in the end to find and highlight the possible cross-border cooperation opportunities toward sustainability and eco-management of the Sharr Mountains in the future.