The impact of aid on per capita income growth has been a particularly controversial topic among researchers and policy-makers alike. Most studies agree that growth would be lower in the absence of aid. This is evident from comprehensive literature surveys of aid and growth studies, including Hansen and Tarp (2000), Morrissey (2001), McGillivray et al. (2006), Mekasha and Tarp (2011) and Clemens et al. (2012). There is no such agreement in this literature regarding what might be described as the contingencies on which the impact of aid on growth is partially dependent. Debate over this topic is intensive and a failure to reach agreement over it is arguably the principal failing of the aid–growth literature owing to the potential guidan...