Even 15 years after the transition from the Organisation of African Unity (OAU) to the African Union (AU), building up and fostering the continental organization remains an ambitious project, both politically as well as financially. The first dimension of political integration has received considerable scholarly attention - in more general terms (see, for instance, Tieku 2004; Khamis 2008; Witt 2012; Williams 2014) but mainly with regard to the emerging African Peace and Security Architecture (APSA, AU 2002 a; see Murithi 2007; Williams 2007; Engel / Gomes Porto 2010, 2013) as well as the complementary but more nascent African Governance Architecture (AGA, AU 2007 a; see, for instance, Engel 2012; Khadiagala 2014; Matlosa 2014). The second dimension of mastering the continental body's finances, however, has so far received only scant attention.In this book, emphasis will be placed on the principles that govern member states' financing of the Union, non-compliance with these principles by some member states, subsequent attempts of introducing compliance and sanctions mechanisms, resulting shifts in member states' contributions to the Union's budget, the composition of this budget, and - in the light of failure to guarantee stable finance for the ambitious AU agenda - increasing donor dependency (in particular in the area of peace and security), and the emerging debate on the need to raise "alternative sources of funding" for the African Union.