The primary purpose of this thesis is to analyze the implications of trade openness or production concentration on firms' performance in a heterogeneous firm framework

Chapter 1 explores the multi-country effects of a varied liberalization exercise on firm productivity. The logic of productivity effects suggests that one nation's trade policy can influence the productivity of firms in other countries

Chapter 2 tests one implication of Melitz (2003) using data on French and Chilean manufacturing firms. Results show that firms that switched from non-exporting to exporting under trade liberalization could be of any size. Therefore they are not concentrated in the middle-size range

Chapter 3 analyzes the effects of local externalities on the probability of starting a new economic activity using firm-level data and geographic information on French zip-codes for 1993-2002. The results show that agglomeration economies at zip-code level strongly influence the location decision of firms