The study discusses the topic of planning decisions taken for the purposes of studies prepared on the municipality level and related to the development of landslide areas in Poland. The aim of the research is to demonstrate the scale of the issue consisting in designating areas at risk of subsidence of soil masses for investment purposes. The research emphasises the essential role of planning documentation in the prevention of investment in such areas. Other vital factors also include the SOPO (Landslide Counteracting System) database as well as the staroste, who, in the course of preparation of planning documentation and issuing decisions on development conditions, issues opinions or agrees (depending on the type of document or decision) on the planned investment in areas at risk of landslides. The study shows the complexity of the spatial planning and development system in Poland and the significant influence of bodies and institutions on the planned development of areas prone to the subsidence of soil masses.