Source: National Statistical Institute of Bulgaria (NSI), 2011
The dynamics of the regional development is mainly determined by the development of the large cities and medium-sized towns in Bulgaria. The highest share in the formation of the national gross value added and gross domestic product have Sofia and the 6th major cities. The network of large cities, which are key centers and generators of growth and development, is unevenly distributed in the territory of the country. This generates and accumulates problems of the kind "center-periphery" and creates conditions for interregional and intra-regional differences/ disparities. There is no doubt that the differences between the Southwestern region and the rest of the NUTS 2 regions, are due to the high rate of development of the capital Sofia. The capital, with its agglomeration area, dominates in the national space much greater than in the past periods and transfers the problem "center-periphery" to the national level.
It is necessary to seek approaches for strengthening the role of the other major cities as balancing centers as well. In the peripheral areas, where there are no large cities, the existing medium towns should take the balancing role and they should be properly stimulated. The network of small and medium-sized towns is developed evenly throughout the country, which is favourably for servicing the rural areas around them. The declining population in these towns and the difficulties in the realization of their economic, social and cultural functions is a troubling phenomenon and calls for serious efforts for their stabilization. The presence of small towns in the rural areas is a factor that is important to be used in future, as it creates opportunities for improvement of the "town-village" connection and for the transformation of the small towns into the urban support centers of the settlement network, that are serving rural areas by offering a wider range of public services.
The already founddisparities inside the regions, (differences between districts and municipalities) are more serious and more clearly expressed. The typical relations as "center - periphery" and the presence of municipalities, lagging behind, as a result of the low capacity and serious difficulties in their demographic, socio-economic and infrastructure development, are to be observed in almost all the regions and districts. These municipalities form a large territorial areas that, according to the criteria of the Regional Development Act, belong to the "areas for targeted support".
The overall socio-economic situation in the municipalities of the large cities and medium-sized towns and their adjoining urban areas is much more favourable, due to better conditions for entrepreneurship and business, better quality of living environment and more accessible and qualified social services. At present, the progress in overcoming the intra- regional disparities/ differences is strongly limited. This statement forces NRDS to pay serious attention to the problem so that it to get into the focus of the regional development policy objectives, with a view the identified disparities to be reduced.