Abstract.The paper briefly investigates theoretical arguments for mismatch unemployment; it presents a vacancy‐unemployment curve for Germany and investigates various reasons for outward shifts of the curve. Both variables, unemployment and vacancies, are decomposed into flows and duration to identify the underlying processes of these shifts. The analysis of the components with the help of change‐duration curves shows adverse trends for unemployment and vacancies over the business cycles. Unemployment duration has increased while vacancy duration has decreased. Mismatch in the labour market can therefore hardly be blamed to have been an obstacle for economic expansion in the German economy during the 1980s. Persistently high unemployment in Germany has to be interpreted as a hysteresis process which was driven by macroeconomic policies, increasing labour supply and restructuring imbedded in the German institutional framew