The purpose of this bachelor thesis is to investigate whether the relationship between interest rate, inflation (measured by CPI), and unemployment in Sweden during the financial crisis of 2007-2010 is consistent with the theoretical assumptions of the Phillips curve, which suggests a negative relationship between inflation and unemployment. The study applies a quantitative approach using two linear regression models (OLS) and supporting correlation analyses. Stationarity was tested using the Augmented Dickey-fuller (ADF) test, which motivated the use of two separate models, one where only non-stationary variables were differenced, and one where all variables were differenced. The results show that changes i the interest rate have a statistically significant negative effect on changes in unemployment in both models, suggesting monetary policy played a role during the crisis period. However, no significant relationship between inflation and unemployment was found, which challenges the applicability of the Phillips curve in this specific context. The findings also highlight the importance of testing for stationarity when working with time series data in econometric analysis.