In Sweden, more than 400,000 individuals are registered with the Swedish Enforcement Authority for debt collection. The authority receives over one million applications for unpaid debts annually. In the first half of 2020, in connection with the outbreak of the pandemic, the number of applications increased by 26 percent compared to the same period the year before, and the total amount of debt also increased steadily. Despite the relatively high prevalence in the population, knowledge of the causes and consequences of over-indebtedness is low. The studies that do exist are mostly based on interviews or survey responses and lack strategies to identify causal outcomes. Most studies focus on the relationship between over-indebtedness and health. Results show, among other things, that over-indebted people are more likely to suffer from depression and chronic illness. The reason for the negative health effects is said to be the increased stress and stigma associated with over-indebtedness. In Sweden, the unique availability of individual data from the Swedish Enforcement Authority enables a systematic study of the effects of over-indebtedness. The research project aims to answer the following questions: (1) Why do individuals become over-indebted? (2) What are the social costs of the large number of over-indebted people in Sweden? By looking at individuals with debt and following their health and labor market outcomes, we can evaluate the negative effects of over-indebtedness. We will also look at whether over-indebtedness increases the risk of crime.