The development of a new AU peace and security architecture attracts much interest today from academic and policy communities alike. Various organizations, not least the UN, are zealously debating the nature of such institutional structures and what best role external actors can play to support and bolster them. Many interesting changes are underway with regards to African security sector reform, combating terrorism and small arms proliferation as well as early warning frameworks. I will focus specifically on one aspect – peacekeeping and peacebuilding capabilities, where there has been a prominent change in emphasis from the Organization of African Unity (OAU) to the AU. Before the end of the cold war the OAU had started putting human beings more and more at the centre of their management of peace and security issues. I provide a broad account of how the OAU was severely constrained in doing so. The AU, since its succession to the OAU in 2002, has continued this transformation in concerns and priorities. As well as elucidating and explaining some background factors to why the AU has started couching its conflict resolution mechanisms in human security language, I analyse to what extent the AU can be an actor for the promotion of human rights and human security. This increasing importance can be seen in many ways but I will focus specifically on the cases of the African Union peace missions in Darfur, Sudan and in Burundi.