In the first chapter of this chapter we explore the heterogeneity in returns to export promotion across countries using a semi-parametric varying coefficient model. In the second chapter we evaluate the impact of terrorist attacks on economic growth while taking into account the mitigating effect of counter-terrorism through a set of strategies and policies deemed to influence the costs, benefits, and opportunity costs of conducting a terrorist attack. In the last chapter we study export dynamics among firms. In particular we explore the possibility that factors beyond productivity level are relevant for the internationalization process of firms. To answer this question we perform a dimension reduction that we previously adapted to account for endogenous factors.