Book excerpt: Global Review of Human Settlements: A Support Paper for Habitat: United Nations Conference on Human Settlement reviews global human settlement conditions and the factors affecting their present and future developments. The report presents information, analyses, and conclusions. It analyzes the causes and effects of the urbanization process; describes the quality of life in human settlements; and presents relevant definitions, list of tables, and country composition by regions. The urbanization process pertains to demographical and economical aspects. Demographical aspects include city size, city growth, migration, and natural increase. Natural population increase accounts for about one-half of urban population while migration from rural to urban places account for the other half. One aspect of the quality of life in human settlements is the prevailing housing conditions. According to the report, housing conditions in most developing countries have become worse in the past ten years due to rapid population growth, to rates of migration from rural to urban places, and to the decline of the rate of increase in national output. The report also contains a list of criteria used nationally to distinguish urban areas from rural areas. For example, South Korea defines urban areas as Seoul or municipalities with 5,000 or more inhabitants. The report is suitable for demographers, economists, environmentalists, ecologists, and policy makers involved in rural development and social services.