“Permeability” is one of the most important characteristics of borders. It is a commonplace that that borders not only divide, but also connect the two territories on either side. Otherwise, the permeability of borders has a large effect on the development of the border areas. Our examination tests this hypothesis using the example of the West Transdanubian Region. During the State-Socialist regime, this area under the shadow of the impermeable Iron Curtain became a typical periphery, where the ruling power hardly sent any resources for development. After the democratic transformation, the Austrian-Hungarian border became semipermeable border, whose connecting and filtering functions slowly came into equilibrium. Finally, after the accession to the European Union in 2004, and, even more so, the Schengen Area in 2004/2007, dominance of contact functions led to a completely open border. In order to better understand this process, our examination tries to quantify the general development level/dynamism of West Hungarian Border Area micro-regions/districts on the basis of Regional Statistical Yearbook of Hungary in 1994, in 2004, and in 2013 – in comparison with the similar data of whole Hungary. We perform this task by using one of the most widespread data reduction methods, Principal Component Analysis (PCA). Although the PCA justifies a positive correlation between the permeability of the borders and the development level/dynamism of the West Transdanubian microregions/districts, we point out significant intra-regional developmental differences between the micro-regions/districts as well, that depends on, in part, their proximity to the border and their degree of urbanization.