The article investigates the relationship between "Interregional Transportation Infrastructures and Regional Development" on a theoretical basis, in the beginning, some theoretical approaches are reviewed, which are on bibliography and are concerned with the relationship mentioned above and then we ere investigating the role of interregional transportation infrastructures in the process of the balancing of regional inequalities, when examined within the context of Regional Development theories. After that, a theoretical proposal about this relationship is formulated, the regional economic effects are classified and the basic factors that favour or influence these effects directly or indirectly are described, and their magnitude as well as their "direction" is determined.
