The German secondary education system is highly stratified. However, the higher tracks have expanded vastly over the last decades, leading to substantial changes in the distribution of students across the different tracks. Following the German re-unification, the school structure itself has also changed to some degree. Furthermore, several smaller education reforms have increased the flexibility of moving between different tracks. This study describes the changing distributions from 1970 to 2006 and examines whether social inequality in lower secondary education outcome and transition to upper secondary education has changed during the process. We find no robust evidence for change in social inequalities in the attainment of lower secondary school-leaving certificates or entry into the various upper secondary options. Most but not all of the observed inequality is due to individuals' lower secondary track placement. (Contains 8 tables, 5 figures, and 21 notes.)