High trade costs inhibit numerous developing countries from fully exploiting the market access opportunities that the multilateral trading system creates. Cumbersome and time-consuming border procedures, obsolete or ill-adapted infrastructure, limited access to trade finance and the complexity and cost of meeting an ever broader array of standards all serve to price too many countries out of international trade. Comparative advantage remains underexploited. Market access does not always convert into market presence. The potential gains from trade are not always fully realised. The Aid-for-Trade Initiative was launched at the 2005 Hong Kong World Trade Organization (WTO) Ministerial Conference to tackle these kinds of constraints and is making headway. The joint OECD-WTO report, Aid for Trade at a Glance 2015, cites many examples of where obstacles are being overcome and the attendant development benefits. Yet more remains to be done. The report calls for a redoubling of efforts to tackle the issue of trade costs which continues to marginalise many of the world’s poorest and most fragile economies.