How does immigration affect export performance? To answer this question, we propose a unified empirical framework allowing to disentangle various mechanisms put forth in previous literature. These include the role of networks in reducing bilateral transaction costs as well as productivity shifts arising from migration-induced knowledge diffusion and increased workforce diversity. While we find evidence supporting all three channels (at both the intensive and the extensive margins of trade), our framework allows to gauge their relative importance. We then focus on diversity and find stronger results in sectors characterized by more complex production processes and more intense teamwork cooperation. This is consistent with theories linking the distribution of skills to the comparative advantage of nations. The results are robust to using a theoretically grounded IV approach combining three variations on the shift share methodology.