sales, and we show that import is even more concentrated than export both within sectors and along the sector and country …

international trade, together with some new facts. First, the availability of information on import and export enables us to … differentiate firms involved in both trading activities - namely two-way traders - from firms that only export, and from those that … only import. We show that firms engaged in both import and export outperform those involved in either importing or …

- namely two-way traders - from firms that only export, and from those that only import. We show that two-way traders have a … export or import. The paper also looks at how the wages and the skill structure of the trading firms change with the country …

control for unobserved firm fixed effects both in the selection and in the export equation, thus identifying the effect on …