“…Increasing tax revenue is a challenge for most lowincome countries because: (a) tax bases are small and narrow; (b) large informal and agricultural (subsistence) sectors; (c) natural resource dependence, and volatility of resource tax revenues; (d) weak tax administrations; (e) the political environment and the influence of interest groups (for example, Besley and Persson, 2014;Mascagni, Moore and McCluskey, 2014;Junquera-Varela, Verhoeven, Shukla, Haven, Awasthi, and Moreno-Dodson, 2017). These challenges allow foreign aid to have direct effects on DRM, not least because aid and taxes are alternative sources of revenue, with the choice between them dependent on domestic political economy factors (Morrissey, 2015). This has bred a huge strand of literature, rather tenuous, exploring the impact of aid on tax effort (measured as the tax/GDP or the revenue/GDP ratio) in developing countries.…”