We derive a simple equation for the welfare gains from trade when tariffs are liberalized or iceberg trade costs fall. Covering various one-sector trade models that may or may not feature extensive margins and imperfect competition, we generalize the analysis of Arkolakis, Costinot and...

The Schengen Agreement has guaranteed unchecked travel across internal EU borders since 1995. Has it also facilitated trade flows? Our econometric analysis suggests that Schengen has boosted trade by 3% on average (equivalent to a drop in tariffs by 0.7 percentage points). Goods trade is more...

The proposed Transatlantic Trade and Investment Partnership (TTIP) is the most significant trade policy initiative since the Uruguay Round (1986 to 1994). It would create a free trade zone covering 45% of world GDP. However, critics dismiss the possible welfare gains as small compared to the...

Arkolakis, Costinot and Rodriguez-Clare (ACR, 2012) prove that, conditional on the change in openness, the welfare gains from foreign trade reforms are quantitatively identical across single-sector trade models with radically different micro-foundations. We generalize this result to domestic and...