The observation of an increase in the ratio of skilled to unskilled wages in the high-income countries and in some cases in low/middle income countries has led to considerable discussion and indeed controversy as to its cause. Virtually none of the analysis has considered a possible role of...

Gains from productivity and knowledge transmission arising from the presence of foreign firms has received a good deal of empirical attention, but micro-foundations for this mechanism are weak . Here we focus on production by foreign experts who may train domestic unskilled workers who work with...