REKK as a member of an international consortium has participated in the Cost Benefit Assessment (CBA) of the network expansion of Montenegro. The assessment included the economic analysis of the new network element: an ENTSO-E compatible CBA assesment and also a Risk and Sensitivity Assessment of various alternatives. It also covered a Financial Impact Assesment of the national TSO, focusing on the financial capabilities of the TSO to undertake and finance the project. A procurement plan according to national and EBRD rules was also created for the investment. As the network expansion aims to enhance RES connection possibilities, its imapcts are assessed in details.