Spatial disparities of social and economic development results in emerging of marginalized (peripheral) areas. Rural areas are particularly exposed to this phenomenon. Peripherality is a multidimensional and complex concept. It is of relative nature and iden tification and determination of peripheral areas is subjective and depends on the identification criteria applied. Peripherality is commonly recognized as a negative phenomenon with such underlying features as backwardness, dependency, marginalization and deprivation. Governments at central and regional levels undertake various actions and public interventions in order to achieve social and territorial cohesion. However, the results of those undertakings are far from satisfactory. The goal of this article is to analyze dimensions of the peripherality of rural areas, especially its economic dimension, and to indicate causes of peripheriality in view of theories and concepts of regional development. This paper is based on the analysis of the literature, public statistics and own research results.