Some issues related to the development of the municipal formations of Irkutsk oblast are considered. It is found that the human population is characterized by the highest sensitivity to impacts of different types, and this factor was used to develop methods of situation analysis of the population response to changes in the socioeconomic environment. The models and methods used are based on notions and equations of reliability theory. The resulting integrated indicator makes it possible to estimate the degree of use of the demographic potential. For the municipal formations of Irkutsk oblast the indicators of integrated life hazard under the existing conditions were calculated on the basis of series of data on the population size for a long period of time. Calculations involve determining the degree of life hazard from the value of demographic response to the impact of multi-level factors of the natural and socioeconomic environment. Results of the calculations identify different trends in the demographic development of cities and districts of Irkutsk oblast discriminating between normal and critical states. A comparative analysis is made of the findings in order to ascertain the characteristics of the transformation of the spatial organization of the territory for the last several decades. General trends for groups of districts and cities, and also some features of differences are revealed. The causes thereof are linked to the inhomogeneity of the region’s socioeconomic conditions. The method of situation analysis presented in this study provides a means of assessing the trends of further development or degradation of settlements. The value of an integrated hazard serves as the indicator of changes in the socioeconomic situation. The suggested technique can be used for historical-demographic comparative analysis and mapping of different regions and stages of their development.Keywords: socioeconomic conditions, demographic situation, integrated hazard, mono-cities, population size, municipal districts.