Upper-middle-income countries (i.e. countries where annual income per capita is roughly between USD 4 000 and 12 000) should be able to finance their Millennium goals themselves. Doing so would require the political will to confront income inequalities and their causes. In contrast, MDGs remain a financial major challenge for low- and lower-middle-income countries (i.e. countries where annual income per capita is approximately below USD 4 000). Filling at least partly these countries’ financing gap through increased private capital flows is a real option. This would, however, require managing their volatility and adapting policy to optimise the social development spillovers. In the foreseeable future, it is doubtful that tax collection can make a significant contribution in the low-income countries with the largest relative needs. If the needs of the poorest citizens of the poorest countries are to be met, all the development resources – aid, private contributions, remittances, domestic taxes and private capital from traditional and emerging partners – will have a role to play. Establishing coherent policies for development will also be crucial.