The unique feature of Russia is its neighbourhood with 16 countries. It means that along with the extraordinary diversity of border regions in landscapes, settlement patterns, economy structure, socio-economic situation, ethnic composition, history, bilateral relations and potential threats to national security, Russia is facing a large set of challenges related with its borders. Strong and acute geopolitical shifts which have occurred over last years resulted in the emergence of fundamentally new challenges to neighborhood. These challenges include, first, the coming into effect since 2015 the treaty on the Eurasian Economic Union (EEU). Second, a sharp decline in relations with neighboring Ukraine due to the incorporation of Crimea to Russia, with the emergency of a new closed state boundary, and civil war in Donbass. Third, the deterioration of relations with the EU and especially its "new" member states – Russian neighbors - Poland and the Baltic States, Western sanctions against Russia and counter-sanctions, which have a direct impact on the situation in Russian border regions. Fourth, Russia's "turn" to the East, in particular, the development of economic ties with the countries in the Asia-Pacific region (APR) and the support for strategic Chinese initiative "One Belt - One Road". Finally, the fall of Russia's national currency's exchange rate, significantly affecting cross-border interactions. The objective of the paper is to summarize the results of three years' work on a project led by the author and supported by Russian Science Foundation and to analyze the impact of borders, integration processes and political challenges at the international and regional level on the development of Russian borderland. The paper is based on an analysis of a comparable statistical data on the territories on both sides of the border. Statistical information was complemented by interviews with experts, sociological polls and personal observations which were used in identifying the typical set of border population activities.

Five major groups of challenges are distinguished – demographic, socio-economic, environmental, institutional, geopolitical and discursive. Demographic challenges are connected to depopulation, the replacement and the negative selection of population, and national identity blurring. Socio-economic challenges are manifested in the appearance of strongly marked socio-economic gradients in the level of socio-economic development and informal cross-border population activity, taking advantage of the border rent. The problem of economic development asynchrony and asymmetry in the conditions of relatively open borders lies in the repartition of resources in sake of a stronger side. Environmental challenges can be seen not only in environmental problems but also in the urgent need in neighbouring countries' cooperative actions to solve them. These actions stumble, firstly, over the absolutisation of national sovereignty and the refusal to coordinate economic decisions concerning the environment; secondly, unsettled conflicts between economic and environmental interests of the sides; thirdly, the continuation of “hydro-technical wars” related with the distribution of the rivers' run-off, the risk of floods and anthropogenic disasters, and water releases, the lack of coordinated regional policy and the mismatch of regional strategies and programmes. Institutional challenges are related to the changing regime and barrier functions of Russia's and adjacent countries' borders as well as the inadequacy of the legal basis of cooperation and cross-border interactions. A quantitative approach to their assessment from the perspective of a Russian citizen travelling abroad was suggested. Geopolitical challenges are provoked by the foci of political instability near Russian borders, the changes in the international political situation, conflicts and mutual claims. One of the main conclusions made from the project is that an important recent trend is the increase of Russian borders' barrier functions matching the general world and European tendency to re-bordering.