Institutional pathologies and the inability of the institutional order of the labor market to adapt to possible changes is manifested in the expansion of the informal segment of labor market and in the distortionof social and labor relations. The author considers theoretical approaches to defining the volume and characteristics of the informal segment of the labor market. Generalized are the advantages and disadvantages of individual methods of estimating informal employment. Using logistic regression, author evaluates the risks of informal employment by socio-demographic characteristics, employment levels and occupation. According to the results of the evaluation, it is proven that the most dangerous age is the youngest and the oldest age groups, as these categories are the most vulnerable and socially unprotected in market conditions. It is those lacking vocational education who have the greatest risk of entering the informal employment segment. The calculations prove that having a vocational education significantly raises the "gain" for women employed in agriculture, and information and telecommunications. It is proven that the structure and level of employment in the formal and informal sectors is an important factor in aggregate labor productivity. By evaluating the aggregate productivity of formal and informal market segments, the author substantiates the importance of the relocation component in terms of economic development prospects. Thus, the calculations prove that the effect of the flow of workers between the informal and formal segments is quite significant for agriculture, trade and construction. While, on the contrary in healthcare, education, transport, and processing, the impact of the intra-industry component on aggregate productivity is greater in comparison to the displacement factor. The weight of the relocation component in the economy as a whole is higher than that of the intra-industry impact factors. Creating an institutional environment that would help reduce the economic activities in the informal segment would objectively promote economic growth.