Abstract
Historically, the trade research field has usually ignored dynamic adjustment of workers, but a recent wave of work has developed a rich set of theoretical and empirical tools to analyze this factor. Empirical approaches have ranged from reduced-form regressions to the structural estimation of underlying parameters, which is necessary to understand welfare effects. A major distinction is that between models that do and those that do not allow for unobserved heterogeneity across workers; these models are useful for different purposes. Consistent findings across methods and countries indicate that costs of switching sectors and occupations are high and that both switching costs and option value are crucial in computing the welfare effects of globalization for workers.