In this article we investigate the empirical relationship between overall specialization and per capita income. The metric we use to measure overall specialization is the median of the sectoral distribution of the Balassa Index of Revealed Comparative Advantages applied to four-digit (SITC rev.2) sectoral export manufactured data for 39 countries over the period 1985 to 2001. Once we take into account countries' specificities using fixed effects GAM, the results of the semiparametric analysis indicate that sectoral diversification of manufactured exports increases monotonically with development, and thus the reconcentration observed at high levels of income in the recent literature may not be linked to trade-induced specialization.