Integrated Public Use Microdata Series-International (IPUMS-International) is an effort to inventory, preserve, harmonize, and disseminate census microdata from around the world. IPUMS-International aims to convert census data from five continents into a uniformly coded and fully documented data series. Nearly all countries included in the data series contribute data from multiple census years. The project uses the same principles and methods that underlie the successful IPUMS-USA model. The data are distributed free of charge via a Web-based data extraction system. Use of the data is restricted to scholarly and educational purposes. The project is conceived as part of a larger enterprise to make the world's microdata available to researchers, encouraging cross-national research with a temporal dimension.