A guidebook that helps government environment officers and customs officials in developing countries decide how to design their own systems to monitor and control importation of ODS by learning from the actual experience of their peers on the South East Asia and Pacific region. It describes the monitoring systems in Australia, Brunei Darussalam, Fiji, Indonesia, Lao P.D.R., Malaysia, Myanmar, New Zealand, the Philippines, Singapore, Sweden, Thailand and Vietnam. It includes Monitoring based on customs statistics; Import permits systems and their role in monitoring imports; Customs role in ensuring compliance with import restrictions; Structure of the Harmonized System; Problems related to mixed chemicals.