Major changes in the global economy, in particular since 1970, have fundamentally affected the incentives facing political and economic elites. Recent research has focused on the impact of increasing global demand for natural resources, which has provided political elites in poor countries with historically unprecedented opportunities to extract high rents from the export of scarce commodities. Moore, Schmidt and Unsworth (2009) suggest that this has provided political elites with “unearned incomes” that have acted to undermine their interest in building effective, accountable public institutions and nurturing economic growth. Foreign aid also provides a source of “unearned income”, and can be associated with substantial corruption, for example in the manipulation of public procurement.