The aim of the paper is to systematize definitive approaches of “problem (distressed) debt” and related terms in order to create a conceptual apparatus useful from the point of view of management entities, as well as to statistically study the dynamics and sectoral structure of problem debt based on the banking sector performance indicators in Russia and other countries in 2009–2023. As a result of the analysis of international and Russian documents in the field of banking regulation, two types of problem debt typologies have been identified: classifications of credit risk of the supervisory authority and recommendations of internal credit risk. Two approaches to the definition of “problem (distressed) debt” have been identified: a regulatory (accounting) approach based on the requirements of regulatory authorities and reporting standards; an identification approach that includes a list of various signs of problems. As a result of the synthesis of approaches, the article proposes the author’s understanding of the terms “overdue debt (credit)”, “problem (distressed) debt” and “problem asset”, taking into account the subject composition of debt managers, represented not only by banks, but also by trade creditors. As part of the preparation of the statistical review for 15 years, a constant excess of the share of “bad” loans (with no probability of repayment and complete depreciation of debt) over “problematic” ones was revealed, which confirms the low effectiveness of the banks’ preventive work to prevent borrowers from becoming problematic (troubled). The authors analyzed the dynamics of the ratio of non-performing loans (NPL) to the total volume of loans issued in 28 countries of the world, revealed a relatively high proportion of the indicator in Russia in recent years. An assessment of the sectoral debt structure of Russian companies showed the dominant position of the manufacturing industry, whereas in the structure of overdue debts, the main companies are from the real estate, wholesale and retail trade sectors. The work of credit institutions to manage problem debts is an important issue of ensuring the economic security of the state and should include monitoring the condition of borrowers based on a strategic map and a comprehensive analysis model, using the methodology of managing transformational projects for the financial recovery of troubled companies.