Although works councils are a core element of the German system of industrial relations, there is little reliable information on their incidence and coverage. This paper uses data from the nationally representative IAB establishment panel to fill this gap. We examine the frequency of works councils by establishment size and broad sector for eastern and western Germany, while at the same time charting the determinants of their presence. Furthermore, we identify newly established works councils and the circumstances of their formation. Finally, we discuss the consequences of our findings for economic analysis of the institution and for public policy.