The authors analyze the organization of employment in nonsimultaneous shifts, considering the shift composition of manufacturing employment, both in the business cycle frequency and in the long run. With regard to the short run, they argue that shiftwork would be procyclical and that this, combined with the inherent lumpiness of shifts, may help resolve the puzzle of the procyclicality of labor productivity. With regard to the long run, the authors identify channels that may account for the increase in shiftwork in the past half-century and for the nonnegative cross-country correlation between shiftwork and the level of income. Copyright 1997 by University of Chicago Press.