Territorisation of Intervention and Use of Endogenic Potentials in Mazovia Development Politics. Mazovia is developing rapidly in comparison to other European regions. It is also the most competitive region in Poland. Nevertheless, it is subject to a serious development duality. The regional policy to date has not been successful in curbing the increasing intraregional disparities. The article serves to indicate possible directions of Mazovia’s development which are worthy of support and fit into the Europe 2020 development model as well as the new EU regional policy paradigm. The adaptation of intervention to the differing parts of Mazovia so as to make use and develop their various endogenic potentials seems to be the right approach to increasing the region’s competitiveness and ensuring a decent standard of life in all its parts.