From the FT this morning:
There are various reasons to be concerned about high aid dependence, but the most worrying is the undermining of good governance by distortion of political accountability. Governments that are highly dependent on aid pay too much attention to donors and too little to their citizens. This might not matter if the interests of citizens and donors were identical. But all donors have some non-developmental motives and, even when they seek to promote development, they have their own priorities. The result is confused and shifting policies, volatile aid and spending and, as a result, slower growth.
I therefore propose that donors collectively set an upper limit on the amount of aid they give to any developing country. This limit should be 50 per cent of the amount of tax revenue that the aid-receiving government raises from its own citizens, by non-coercive means and excluding revenue from oil and minerals.
Well worth reading in full.