Demographic and Health Surveys (DHS)
The DHS is a project funded by the United States Agency for International Development to promote better gathering of survey data on health issues pertaining to family life and reproductive health in developing countries. Aggregated data from DHS surveys are readily accessible via the STATcompiler interface that allows for on-line visualization and for download in tabular form. Microdata files from the surveys are also available upon registration and application for access. Harmonized extracts of selected DHS modules are available via https://www.idhsdata.org/idhs/.
Family Planning and Reproductive Health Indicators Database
UNC-Chapel Hill hosts an inventory of indicators commonly used in monitoring and evaluation efforts by NGO’s and international organizations. The database does not provide actual data themselves, but does explain how indicators are measured/constructed and where the data come from in terms of sources and aggregation. The database is thus quite useful as a source of ideas and inspiration for how to craft questions for evaluation surveys and data-collection instruments.
Global Health Data Exchange (GHDx)
The Global Health Data Exchange is an undertaking by the Institute for Health Metrics and Evaluation (IHME) and is a "comprehensive catalog of surveys, censuses, vital statistics, and other health-related data." While it is not a data archive and thus does not necessarily provide access to specific data resources, it is a very useful tool for locating health/demographic data at both the micro- and macro- levels. The IHME has various other data-related projects, including its estimates of Global Burden of Disease.
International Household Survey Network (IHSN)
The IHSN is devoted to improving "the availability, accessibility, and quality of survey data within developing countries, and to encourage the analysis and use of this data by national and international development decision makers, the research community, and other stakeholders." As part of this mission, the IHSN has developed a very useful catalog of household surveys that covers both national and international surveys. The catalog allows users to filter by country, date range, and availability, and to search through variable descriptions and question texts. The IHSN also provides guidance and tips for designing, collecting, and managing survey data.
Integrated Public Use Microdata Series (IPUMS) International
The IPUMS International project at the University of Minnesota provides access to samples from population censuses in various countries, with the data harmonized and standardized for easier cross-national comparisons. The list of available samples is located at https://international.ipums.org/international/samples.shtml.
Living Standards Measurement Study
The Living Standards Measurement Study, from the World Bank. See the "LSMS Survey Finder" to search through their inventory of studies. Note that the site also offers tips and methodological guidance for working with microdata files and for conducting household surveys. Records for individual studies will provide documentation (e.g. user guides, survey instruments) and information about access to the data themselves.
World Bank Microdata Central Microdata Catalog
The World Bank has its own microdata catalog, with the focus on data collected by the World Bank itself (with some exceptions). As with the IHSN, users can search through variable-level information (e.g. survey questions) for particular terms and phrases and the like. The catalog is within the Bank's Microdata Library.