Continued rapid industrialization is expected to make East Asia the largest source region for air pollution in the coming decades. This chapter reviews the import and export of air pollutants, mainly carbon monoxide and ozone, by long-range transport to and from East Asia. Air pollutant sources and transport characteristics dominated by the monsoon regime over Northeast and Southeast Asia are summarized. Over Northeast Asia both import and export of air pollution contribute significantly to the intercontinental transport of pollution. Trans-Eurasian transport of air pollution by westerly flows from Europe to Northeast Asia, and trans-Pacific transport of Northeast Asian pollution to the Pacific and North America have been verified by both observations and model studies. The influence of Siberian forest fires on pollutants over Northeast Asia has also been clearly identified. Over continental Southeast Asia, import of air pollution occurs mainly from source regions over the Indian subcontinent during the summer monsoon and from Northeast Asia during the early winter monsoon. Biomass burning within the region, however, strongly dominates regional pollution. The transoceanic export of air pollution from Southeast Asian biomass burning is known to be one of the most significant sources of ozone and CO over the North Pacific in the springtime.