The influence of anthropogenic trace gas emissions on the global troposphere is controlled by both chemical and dynamical processes, and the interaction between them controls any long-range impacts. We use the FRSGC-UCI 3-D chemical transport model to quantify the effects of anthropogenic emissions from the developing countries of East Asia on neighbouring continents and on the global troposphere. We show how the coupling of chemistry and meteorology leads to the largest changes in ozone over North America and Europe in spring and autumn, and demonstrate that future increases in precursor emissions may be expected to have significant effects on background levels of ozone at a hemispheric scale.