This paper provides an analysis of the pollution intensity of US manufacturing production and imports from 1995-2005 and determines whether US patterns can be observed in other developed economies, in particular the European Union. The results show that in the 1990s, US and EU manufacturing production increasingly specialized in clean goods – a “green” shift. However, in the 2000s the trend reversed as both regions increasingly specialized in pollution-intensive goods – a “brown” shift. Still, the shifts in composition were small, especially for the United States. The cleanups of US and EU manufacturing were overwhelmingly driven by improvements in technology. In the United States, about a quarter of the cleanup can be explained by increased imports of polluting goods, and imports from lower-middle income countries exhibited a brown shift. Those two facts combined suggest that the United States might be offshoring pollution to lower-middle income countries. In the European Union, however, there is little evidence of pollution offshoring. In fact, a portion of the brown shift of EU manufacturing production can be matched by increased exports of polluting EU goods.