The Volume 9 of Sources and Methods: International Labour Migration presents the sources and methods used in the compilation of international labour migration statistics, based on the ILO metadata survey conducted in 2015-2016 in ILO Member countries and territories.

The purpose of this volume is twofold: first, to describe the questionnaire and results of the ILO metadata survey; and second, to provide detailed information for each country on the sources of data related to international labour migration, the coverage of the data, the type of information collected, the concepts, definitions and classifications used, and the methods of data collection and dissemination used in each data source and on methodological issues.

The analysis of the metadata gathered through the ILO metadata country survey is presented in a separate ILO report entitled "Analysis of the ILO country survey on international migrant workers".