In the midst of the atrocities reported in the Democratic Republic of Congo, the seemingly constant strife in the Horn of Africa, and the ongoing violence in Darfur, how do we make sense of the simultaneous increase in interstate security cooperation in Africa? Benedikt Franke assesses the peace and security architecture that is taking shape under the nominal leadership of the African Union, analysing the emerging structures and trends and also rethinking prevailing notions and theoretical assumptions about interstate security relations.