This article reviews the empirical evidence on firm heterogeneity in international trade. A first wave of empirical findings from microdata on plants and firms proposed challenges for existing models of international trade and inspired the development of new theories emphasizing firm...

This paper reviews the empirical evidence on firm heterogeneity in international trade. A first wave of empirical findings from micro data on plants and firms proposed challenges for existing models of international trade and inspired the development of new theories emphasizing firm...

This paper reviews the empirical evidence on firm heterogeneity in international trade. A first wave of empirical findings from micro data on plants and firms proposed challenges for existing models of international trade and inspired the development of new theories emphasizing firm...

Unit values of US imports at the product level reveal a substantial degree of vertical product differentiation among countries exporting to the US. This specialization is not apparent by looking solely at trade flows. Two trends stand out. First, the portion of US import products originating in...