About one third of rural areas in Poland have been classified by planners as problem areas. These are usually peripheral and marginalized areas, characterized by a number of deficits (physical, human, social and cultural capital), which cannot develop without external assistance and have problems even with formulating development goals. The challenges posed by the new paradigm: sustainable rural development, referring to many elements of the sociological concept of neo-endogenous development, are particularly important. The author, characterizing the deficits of problem areas, emphasizes the importance of human, social and cultural deficits. This is the context of the issue of external assistance for these areas: its nature and the limits of social rationality. Gerlind Weber's concept of the negative development spiral and the new development paradigm she proposes for some of these areas (the matching paradigm) are useful in explaining the described phenomena.