The term Asia is used here in a restricted sense to include the countries from India to the Pacific, bounded in the north by China, South Korea and Japan and in the south by Indonesia. This region contains approximately 2.7 billion people, about a half of the worldâs population. If any single factor could be said to describe this research environment, it is diversity. At one end of the spectrum are countries where market research has yet to gain any real foothold, among them being Myanmar (Burma), Laos and Cambodia. Some, such as Vietnam, are at the emergent stage. But most have research industries of several decadesâ standing, the full range of research services, and sampling and research methodology as sophisticated and variegated as western practice. The countries in this region certainly vary widely in the challenges they present for general population sampling, which are described below under five headings: 1. population characteristics; 2. information sources; 3. selection methods; 4. practical issues; 5. response rates.