Trade policy constitutes one of the most important chapters in any economic history account of the early years of this century. To assess its impact on the economic development of individual countries we need comparative measures of protection at the sectoral level. This paper offers what appears to be the first attempt to construct such measures for 1913 based on the Heckscher-Ohlin trade model. It uses a newly constructed data set on net trade flows and factor endowments covering fourteen ‘old world’ and four ‘new world’ economies. In contrast to previous studies, the measures suggested here are, first, objective in the sense of not attempting to classify a priori the trade regime of some country based only on its tariff legislation. Second, they reflect all types of trade interventions. Third, they are constructed as continuous measures. Finally, and most importantly, they are comparable across countries and sectors.