Among other factors, public policy is influenced by the debates that take place in a policy subsystem. Discourse network analysis is a methodology for the empirical description of changes in policy debates over time and for drawing inferences on how political discourse works. The presentation introduces the methodological toolbox of discourse networks and its application to pre-Riester pension politics in Germany. Among other findings, there is one closed policy community until the mid-1990s while increasing polarization occurs between this community and a new advocacy coalition composed of financial-sector actors and employers' associations towards the end of the 1990s. These trends culminate in an erosion of the old coalition before major policy change takes place in 2001.